Nutrition and health

Objectives:
Dietary fat may play a role in lung carcinogenesis. Findings from epidemiologic studies, however, remain inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Is there an association between dietary fat intake and the risk of lung cancer?

Study design:
This review article included 10 prospective cohort studies with a total of 1,445,850 participants, of which 18,822 incident cases (subjects with lung cancer).

The mean follow-up was 9.4 years. 

Results and conclusions:
The investigators found high intakes of total fat were associated with a 7% significant increased risk of lung cancer [for highest v lowest quintile: HR = 1.07, 95% CI = 1.00 to 1.15].

The investigators found high intakes of saturated fat were associated with a 14% significant increased risk of lung cancer [for highest v lowest quintile: HR = 1.14, 95% CI = 1.07 to 1.22].

The investigators found high intakes of saturated fat were associated with a 23% significant increased risk of lung cancer among current smokers [for highest v lowest quintile: HR = 1.23, 95% CI = 1.13 to 1.35, p for trend 0.001].

The investigators found high intakes of saturated fat were associated with a 61% significant increased risk of squamous cell lung cancer [for highest v lowest quintile: HR = 1.61, 95% CI = 1.38 to 1.88].

The investigators found high intakes of saturated fat were associated with a 40% significant increased risk of small cell carcinoma lung cancer [for highest v lowest quintile: HR = 1.40, 95% CI = 1.17 to 1.67].

The investigators found a high intake of polyunsaturated fat was associated with a 8% significant decreased risk of lung cancer [for highest v lowest quintile: HR = 0.92, 95% CI = 0.87 to 0.98, p for trend = 0.02].

The investigators found a 5% energy substitution of saturated fat with polyunsaturated fat was associated with a 16% and 17% lower risk of small cell and squamous cell carcinoma, respectively.

The investigators found no associations for monounsaturated fat.

The investigators concluded that high intakes of polyunsaturated fat decrease risk of lung cancer, while high intakes of saturated fat increase risk of lung cancer, particularly among smokers and for squamous cell and small cell carcinoma.

Original title:
Dietary Fat Intake and Lung Cancer Risk: A Pooled Analysis by Yang JJ, Yu D1, […], Shu XO.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28742456

Additional information of El Mondo:
Find more information/studies on fat and cancer right here.

A daily diet with high intakes of saturated fat is a diet that is largely made up of meals/products with more than 10 En% saturated fat, with a small part of meals/products with less than 10 En% saturated fat. Practically, this means that all meals/products that you eat on a daily basis should contain on average more than 10 En% saturated fat.
Check here which products contain more than 10% En% saturated fat.

A daily diet with low intakes of saturated fat is a diet that is largely made up of meals/products with less than 7 En% saturated fat, with a small part of meals/products with more than 7 En% saturated fat. Practically, this means that all meals/products that you eat on a daily basis should contain on average less than 7 En% saturated fat.
Check here which products contain less than 7% En% saturated fat.

Objectives:
The relationships between metabolic syndrome (MetS) and risk of incident stroke are inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does metabolic syndrome increase risk of stroke?

Study design:
This review article included a total of 16 prospective cohort studies, including 116,496 participants who were initially free of cardiovascular diseases.

Results and conclusions:
The investigators found comparing the persons without metabolic syndrome, those with metabolic syndrome had a significantly higher risk of 70% for incident stroke [pooled relative risk (RR) = 1.70, 95% CI = 1.49-1.95]. Significant means that there is an association with a 95% confidence.

The investigators found in subgroup analyses that women with metabolic syndrome had a significantly higher risk of 83% for incident stroke [pooled relative risk (RR) = 1.83, 95% CI = 1.31-2.56]. Significant because RR of 1 was not found in the 95% CI of 1.31 to 2.56. RR of 1 means no risk/association.

The investigators found in subgroup analyses that men with metabolic syndrome had a significantly higher risk of 47% for incident stroke [pooled relative risk (RR) = 1.47, 95% CI = 1.22-1.78].

The investigators found in subgroup analyses that those with metabolic syndrome had a significantly higher risk of 112% for ischemic stroke [pooled relative risk (RR) = 2.12, 95% CI = 1.46-3.08].

The investigators found in subgroup analyses that those with metabolic syndrome had a non-significantly higher risk of 48% for hemorrhagic stroke [pooled relative risk (RR) = 1.48, 95% CI = 0.98-2.24].

The investigators concluded metabolic syndrome increases risk of stroke, particularly among women and those with ischemic stroke.

Original title:
Metabolic syndrome and stroke: A meta-analysis of prospective cohort studies by Li X, Li X, […], Gao Q.

Link:
http://www.sciencedirect.com/science/article/pii/S0967586816311079

Additional information of El Mondo:
Find more information/studies on overweight and cardiovascular disease right here. 

Find out whether you are overweight or not right here.

Those with metabolic syndrome are advised to select the following food items.

Objectives:
Nutritional supplements may be important on cognition but the evidence is heterogeneous. Therefore, this review article (meta-analysis) has been conducted.

Do both childhood nutritional supplementation and antenatal nutritional supplementation improve cognitive development of children in developing countries?

Study design:
This review article included 48 studies with 29814 children (16944 and 12870 children were in the intervention and control arms, respectively) from 20 developing countries.
Childhood nutritional supplements included iron (25 interventions), zinc (23), folic acid (18), lipid/fat (13), calcium (14), vitamin A (14), vitamin B2 (13), protein (11) and vitamins B1, B3, B12 (9).
Antenatal nutritional supplements given to mothers during pregnancy included zinc (15), iron (10), vitamin A (10), vitamins B1, B2, B3, B12 (10), vitamin C (9) and iodine and selenium (8).
Funnel plots and Egger regression tests showed no publication bias in both childhood and antenatal supplementation.

Results and conclusions:
The investigators found childhood nutritional supplementation significantly improved children's cognitive development [d = 0.05, 95% CI = 0.004-0.10, p = 0.03, n = 44] and those with ≥5 nutrients was particularly beneficial [d = 0.15, 95% CI = 0.08-0.22, p  0.0001, n = 16].

The investigators found antenatal nutritional interventions non-significantly improved children's cognitive development [d = 0.02, 95% CI = -0.01 to 0.06, p = 0.20, I2 = 47.45%, p  0.0001, n = 23].

The investigators found timing of nutritional supplements was also associated with the cognitive benefits of supplementation.
Antenatal supplementation appeared to have the strongest benefit when started in the first trimester of pregnancy [d = 0.15, 95% CI = 0.03-0.28, p = 0.02, n = 4]; supplementation started later did not yield any significant benefits.
Similarly, supplementation on children aged 6-18 months had significant benefit [d = 0.09, 95% CI = 0.02-0.15, p = 0.009, n = 27] whereas those of older children did not [d = 0.04, 95% CI = -0.06 to 0.16, p = 0.37, n = 15].

The investigators found duration of follow-up (i.e. the time between intervention completion and outcome assessment) was significantly associated with the benefits of antenatal supplementation.
Interventions with ≥5 years of follow-up had significantly stronger benefits [d = 0.10, 95% CI = 0.02-0.19, p = 0.02, n = 5] than the others [d = 0.005, 95% CI = -0.04 to 0.05, p = 0.94, n = 19].
Such phenomenon was not observed in childhood supplementation.

The investigators found in childhood interventions, several nutrient types were associated with cognitive benefits:
-iron [d = 0.09, 95% CI = 0.03-0.15, p = 0.01, n = 25];
-zinc [d = 0.09, 95% CI = 0.02-0.15, p = 0.01, n = 23];
-calcium [d = 0.14, 95% CI = 0.07-0.21, p = 0.0002, n = 14];
-vitamin B2 [d = 0.11, 95% CI = 0.03-0.19, p = 0.01, n = 13] and
 -protein [d = 0.13, 95% CI = 0.03-0.22, p = 0.01, n = 11].

The investigators found in antenatal supplementation, several nutrient types were associated with cognitive benefits:
 -iron [d = 0.05, 95% CI = 0.002-0.10, p = 0.04, n = 10];
-vitamins B1, B2, B3, B12 [d = 0.05, 95% CI = 0.01-0.10, p = 0.02, n = 10] and
-vitamin C [d = 0.07, 95% CI = 0.02-0.12, p = 0.004, n = 9].

The investigators concluded childhood nutritional supplementation, especially those with ≥5 nutrients, is effective in improving cognitive development of children in developing countries. However, future supplementation should aim to provide multiple nutrients to younger children and pregnancy women at the first trimester. To identify the optimal supplementation, future studies should include both short- and long-term assessments on the cognitive performance of children and consider the potential interactive effects of different nutrients.

Original title:
Impact of nutritional supplements on cognitive development of children in developing countries: A meta-analysis by Ip P, Ho FKW, […], Hon KL.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5587553/

Additional information of El Mondo:
Find more information/studies on food fortification/malnutrition, pregnancy, vitamins and minerals right here.
 

Objectives:
Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DTP) and standard titre measles containing vaccines (MCV) have prevented countless illnesses and deaths among infants and children worldwide, especially those living in the world’s poorest countries.

The objectives of this review article are to review evidence on associations between receipt of these vaccines and childhood mortality, with a focus on effects beyond those attributable to the targeted diseases.

Study design:
This review article included 34 birth cohort studies (17 birth cohorts for BCG vaccine, 17 birth cohorts for DTP vaccine and 27 birth cohorts for MCV. 5 results for BCG vaccine were from clinical trials, as were 4 results for MCV. Three, zero and seven articles reported results for non-specific mortality for BCG, DTP and MCV, respectively).
Most studies reported on all cause (rather than non-specific) mortality.
Ages at MCV vaccination were available, they were typically around 9 months, ranging from 4.5 months in a clinical trial to median 15.8 months in a cohort study.
There was insufficient evidence to determine whether any difference exists in effect of DTP according to vitamin A supplementation status.

Results and conclusions:
The investigators found in 5 clinical trials that BCG vaccine non-significantly reduced all cause mortality with 30% [average relative risk = 0.70, 95% CI = 0.49 to 1.01].

The investigators found in 9 observational studies at high risk of bias that BCG vaccine significantly reduced all cause mortality with 53% [average relative risk = 0.47, 95% CI = 0.32 to 0.69, I2 = 63%].

The investigators found in 10 studies at high risk of bias that DTP vaccine (almost always with oral polio vaccine) non-significantly increased all cause mortality with 38% [relative risk = 1.38, 95% CI = 0.92 to 2.08]; this effect seemed stronger in girls than in boys.

The investigators found in 4 clinical trials that standard titre MCV non-significantly decreased all cause mortality with 26% [relative risk = 0.74, 95% CI = 0.51 to 1.07, I2 = 0%]; this effect seemed stronger in girls than in boys.

The investigators found in 18 observational studies at high risk of bias that standard titre MCV significantly decreased all cause mortality with 49% [relative risk = 0.51, 95% CI = 0.42 to 0.63, I2 = 64%]; this effect seemed stronger in girls than in boys.

The investigators found in 7 observational studies at high risk of bias that administering DTP with or after MCV may be associated with higher mortality than administering it before MCV.

The investigators concluded evidence suggests that receipt of BCG and MCV reduce overall mortality by more than would be expected through their effects on the diseases they prevent, and receipt of DTP may be associated with an increase in all cause mortality. Although efforts should be made to ensure that all children are immunised on schedule with BCG, DTP and MCV, randomised trials are needed to compare the effects of different sequences.

Original title:
Association of BCG, DTP, and measles containing vaccines with childhood mortality: systematic review by Higgins JP, Soares-Weiser K, […], Reingold AL.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5063034/

Additional information of El Mondo:
Find more information/studies on food fortification/malnutrition right here.
 

Objectives:
Polyunsaturated fats (PUFAs) have been shown to reduce type 2 diabetes (T2DM) risk and improve insulin responsiveness in T2DM subjects, but whether the plant sources of omega-3 PUFA (alpha-linolenic acid [ALA]) have an effect on glycemic control requires further investigation. Therefore, this review article (meta-analysis) has been conducted.

Does alpha-linolenic acid dietary intake reduce diabetes risk?

Study design:
This review article included a total of 8 RCTs involving 212 participants with type 2 diabetes.
5 trials (62.5%) were parallel designs and 3 (37.5%) were crossover designs.
Participants were generally middle-aged (median age  =  54 years, range  =  47-64 years) and overweight or obese (median BMI  =  30.7, range  =  28.0-33.2).
Overall, participants had controlled diabetes (median HbA1c = 6.8%, median FBG = 7.95 mmol/L) and the majority of studies indicated the use of hypoglycemic drugs or other medications, although all studies excluded the use of insulin therapy.
The dose of ALA ranged from 1.5 to 7.4 g/day with a median assigned dose of 4.4, 5.4 and 5.4 g/day of ALA for trials that reported HbA1c, FBG and FBI, respectively.
The median duration of the treatment was 3 months, ranging from 2 to 12 months.
7 studies (87.5%) were considered high quality (MQS ≥8).

Results and conclusions:
The investigators found compared to a control diet, a median dose of 4.4 g/day of alpha-linolenic acid intake for a median duration of 3 months did not affect HbA1c (%) of patients with type 2 diabetes [MD =  -0.01, 95% = -0.32 to 0.31, p  =  0.96].

The investigators found compared to a control diet, a median alpha-linolenic acid dose of 5.4 g/day did not lower fasting blood glucose (FBG) of patients with type 2 diabetes [MD  = 0 .07, 95% CI = -0.61 to 0.76, p  = 0 .84] or fasting blood insulin (FBI) of patients with type 2 diabetes [MD  =  7.03, 95% CI = -5.84 to 19.89, p  = 0 .28].

The investigators found summary effect estimates were generally compromised by considerable and unexplained heterogeneity [I2 ≥ 75%].

The investigators found in the subgroup analysis of continuous predictors, a reduction in HbA1c (%) and FBG (mmol/L) was significantly associated with an increased intake of ALA.

The investigators found further adjustment for publication bias using Duval and Tweedie's trim-and-fill analysis provided an adjusted, significant MD of 0.25 [95% CI = -0.38 to -0.12, 0.001) for HbA1c (%).

The investigators concluded alpha-linolenic acid-enriched diet with a median alpha-linolenic acid dose of 4.4 g/day during 3 months has no effects on HbA1c, FBG or FBI in patients with type 2 diabetes. The scarce number of existing RCTs and the presence of heterogeneity in the meta-analysis limit the ability to make firm conclusions about alpha-linolenic acid in type 2 diabetes management. The potential for alpha-linolenic acid to have dose-dependent effects warrants further research in this area.

Original title:
The effect of alpha-linolenic acid on glycemic control in individuals with type 2 diabetes: A systematic review and meta-analysis of randomized controlled clinical trials by Jovanovski E1, Li D, […], Vuksan V.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5457843/

Additional information of El Mondo:
Find more information/studies on PUFA and diabetes right here.

4.4 g/day alpha-linolenic acid can be achieved by taking 1 to 2 tablespoons of flax or salba-chia seeds or about 12 whole walnuts per day.

 

Objectives:
Four studies previously indicated that the effect of malaria infection during pregnancy on the risk of low birthweight (LBW 2,500g) may depend upon maternal nutritional status. Therefore, this review article has been conducted.

Does malaria during pregnancy increase risk of having a low birthweight and is there a synergistic interaction between malaria and malnutrition?

Study design:
This review article included pooled data from 14,633 pregnancies from 13 studies (6 cohort studies and 7 randomized controlled trials) conducted in Africa and the Western Pacific from 1996-2015.

The major limitations of the study included availability of only 2 cross-sectional measurements of malaria and the limited availability of ultrasound-based pregnancy dating to assess impacts on preterm birth and fetal growth in all studies.

Results and conclusions:
The investigators found the adjusted risk of delivering a baby with a low birthweight was 8.8% among women with malaria infection at antenatal enrollment compared to 7.7% among uninfected women [adjusted risk ratio = 1.14, 95% CI = 0.91 to 1.42, n = 13,613 pregnancies].

The investigators found the adjusted risk of delivering a baby with a low birthweight was 10.5% among women with malaria infection at delivery compared to 7.9% among uninfected women [adjusted risk ratio = 1.32, 95% CI = 1.08 to 1.62, n = 11,826 pregnancies].

The investigators found the adjusted risk of delivering a baby with a low birthweight was 15.3% among women with low mid-upper arm circumference (MUAC 23 cm) at enrollment compared to 9.5% among women with MUAC ≥ 23 cm [adjusted risk ratio = 1.60, 95% CI = 1.36 to 1.87, n = 9,008 pregnancies).

The investigators found the adjusted risk of delivering a baby with a low birthweight was 17.8% among women with both malaria infection and low mid-upper arm circumference at enrollment compared to 8.4% among uninfected women with mid-upper arm circumference ≥ 23 cm [joint adjusted risk ratio = 2.13, 95% CI = 1.21 to 3.73, n = 8,152 pregnancies].

The investigators found no evidence of synergism (i.e., excess risk due to interaction) between malaria infection and mid-upper arm circumference on the multiplicative [p = 0.5] or additive scale [p = 0.9]. Results were similar using body mass index (BMI) as an anthropometric indicator of nutritional status.

The investigators found meta-regression results indicated that there may be multiplicative interaction between malaria infection at enrollment and low mid-upper arm circumference within studies conducted in Africa. However, this finding was not consistent on the additive scale, when accounting for multiple comparisons or when using other definitions of malaria and malnutrition. 

The investigators concluded pregnant women with malnutrition and malaria infection are at increased risk of low birthweight compared to women with only 1 risk factor or none, but malaria and malnutrition do not act synergistically.

Original title:
Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data by Cates JE, Unger HW, […], Rogerson S.

Link:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5549702/

Additional information of El Mondo:
Find more information/studies on food fortification/malnutrition and pregnancy right here.
 

Objectives:
Available studies in the literature on the selenium levels in Alzheimer's disease (AD) are inconsistent with some studies reporting its decrease in the circulation, while others reported an increase or no change as compared to controls. Therefore, this meta-analysis (review article) has been conducted.

Do lower circulatory (plasma/serum and blood), erythrocyte and cerebrospinal fluid (CSF) selenium levels increase Alzheimer's disease risk?

Study design:
This review article included 12 case-control/observational studies reporting selenium concentrations in Alzheimer's disease and controls.

Results and conclusions:
The investigators found random-effects meta-analysis indicated a decrease in circulatory [SMD = -0.44], erythrocellular [SMD = -0.52] and cerebrospinal fluid [SMD = -0.14] selenium levels in Alzheimer's disease patients compared to controls

The investigators found stratified meta-analysis demonstrated that the selenium levels were decreased in both the subgroups with [SMD = -0.55] and without [SMD = -0.37] age matching between Alzheimer's disease and controls.

The investigators also found a direct association between decreased selenium levels and glutathione peroxidase (GPx) in Alzheimer's disease.

The investigators concluded that circulatory selenium concentration is significantly lower in Alzheimer's disease patients compared to controls and this decrease in selenium is directly correlated with an important antioxidant enzyme, the glutathione peroxidase, in Alzheimer's disease.

Original title:
A systematic review and meta-analysis of the circulatory, erythrocellular and CSF selenium levels in Alzheimer's disease: A metal meta-analysis (AMMA study-I) by Reddya VS, Bukkeb S, […], Pandeye AK.

Link:
http://www.sciencedirect.com/science/article/pii/S0946672X1630205X%20

Additional information of El Mondo:
Find more information/studies on selenium and dementia right here.
 

Objectives:
Recently, several randomized controlled trials (RCTs) reported the association between the use of vitamin or antioxidant supplements and the risk of bladder cancer. However, those findings remain inconsistent and some studies even reported that vitamin and antioxidant supplements increased the risk of bladder cancer. Therefore, this review article (meta-analysis) has been conducted.

Is there an association between the use of vitamin or antioxidant supplements and the risk of bladder cancer?

Study design:
This review article included 14 RCTs with a total of 147,383 participants, which involved 89,972 in the supplement group and 57,411 in the control group.

The supplementation and follow-up periods ranged between 1 and 13 years.

The types of vitamin and antioxidant supplements were as follows: vitamin A, vitamin B6, vitamin C, vitamin D, vitamin E, beta-carotene, folic acid and selenium.
The dosage regimens in individual trials were as follows: vitamin A (200 mg or 25,000, 36,000 or 40,000 IU daily), vitamin B6 (25 or 100 mg daily), vitamin C (2,000 mg daily), vitamin D (1,600 IU daily), vitamin E (50 mg or 400 IU daily), beta-carotene (20 or 30 mg daily; 50 mg alternate day; 75 mg daily for 3-month cycles), folic acid (1.6 mg daily) and selenium (200 μg daily).

Publication bias was not observed [Begg's funnel plot, symmetrical and Egger's test, p for bias = 0.378].

Results and conclusions:
The investigators found in fixed-effect meta-analysis of all 14 trials that vitamin or antioxidant supplementation was not associated with the risk of bladder cancer [RR = 1.04, 95% CI = 0.92-1.17, I2 = 39.7%].

The investigators found regarding types of supplements, any type of vitamin and antioxidant supplements had no beneficial effect on the risk of bladder cancer:
-vitamin A [RR = 0.86, 95% CI = 0.65-1.13, I2 = 61.7%, n = 5];
-vitamin B6 [RR = 0.77, 95% CI = 0.49-1.20, I2 = 78.8%, n = 3];
-vitamin C [RR = 0.74, 95% CI = 0.36-1.54, I2 = 88.8%, n = 2];
-vitamin D [RR = 1.05, 95% CI = 0.85-1.29, n = 1];
-vitamin E [RR = 0.91, 95% CI = 0.69-1.19, I2 = 60.9%, n = 6];
-beta-carotene [RR = 1.19, 95% CI = 0.96-1.46, I2 = 0.0%, n = 6];
-folate [RR = 1.05, 95% CI = 0.85-1.29, n = 1] and
-selenium [RR = 1.09, 95% CI = 0.81-1.46, I2 = 0.0%, n = 2].

The investigators found overall, there was no significant effect of vitamin and antioxidant supplements in the subgroup meta-analyses by various factors such as dose of supplements, type of cancer prevention, methodological quality, duration of treatment, provider of supplements, type of control and number of participants.
However, the risk of bladder cancer was marginally increased in trials with the use of beta-carotene alone [RR = 1.44, 95% CI = 1.00-2.09, I2 = 0.0%, n = 3].

The investigators concluded that vitamin and antioxidant supplements have no overall preventive effect against bladder cancer. Instead, subgroup meta-analyses showed that beta-carotene supplementation marginally increased the risk of bladder cancer. Even though further large, high-quality trials are required to confirm these associations, the effects (either beneficial or harmful) of vitamin or antioxidant supplements on bladder cancer should not be overemphasized.

Original title:
Effects of Vitamin and Antioxidant Supplements in Prevention of Bladder Cancer: a Meta-Analysis of Randomized Controlled Trials by Park SJ, Myung SK, […], Lee YJ.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5334161/

Additional information of El Mondo:
Find more information/studies on vitamins, selenium, beta-carotene, antioxidants and cancer right here.

Objectives:
Measles is an important cause of childhood morbidity and mortality globally, despite increasing vaccine coverage. Zinc plays a significant role in the maintenance of normal immunological functions, therefore supplements given to zinc-deficient children will increase the availability of zinc and could reduce measles-related morbidity and mortality. This is an update of a review first published in 2015.

Does zinc supplementation reduce measles risk in children?

Study design:
This review article included 1 RCT conducted in India, involving 85 children diagnosed with measles and pneumonia.

Results and conclusions:
The investigators found in the trial conducted in India no significant difference in mortality between children with measles and pneumonia who received zinc supplements and those who received placebo [RR = 0.34, 95% CI = 0.01 to 8.14].

The investigators also found no significant difference in time to absence of fever between children who received zinc supplements and those who did not [HR = 1.08, 95% CI = 0.67 to 1.74].

The investigators also found no treatment-related side effects in either group and the overall quality of the evidence was very low.

The investigators concluded no definitive conclusions can be drawn from this review about the effects of zinc supplementation on clinical outcomes of children with measles due to the very low quality of the evidence available. There is insufficient evidence to confirm or refute the effect of zinc supplementation in children with measles.

Original title:
Zinc supplementation for the treatment of measles in children by Awotiwon AA, Oduwole O, […], Okwundu CI.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28631310

Additional information of El Mondo:
Find more information/studies on food fortification/malnutrition and zinc right here.

Objectives:
Protective effects of calcium supplementation against colorectal adenomas have been documented in systematic reviews; however, the results have not been conclusive. Therefore, this review article (meta-analysis) has been conducted.

Does calcium supplementation reduce colorectal adenomas?

Study design:
This review article included 5 RCTs involving 2,234 patients with a history of adenomas.
Based on visual inspection of the funnel plots as well as on quantitative measurement that used the Egger regression test, there was weak evidence of publication bias.
No major serious adverse events were associated with the use of calcium, but there was an increase in the incidence of hypercalcemia [p  = 0 .0095].
Random errors were evaluated with trial sequential analyses (TSAs). However, TSA indicated a lack of firm evidence for a beneficial effect of calcium supplementation.

Results and conclusions:
The investigators found quantitative pooling of results from all 5 RCTs indicated that the use of supplemental calcium lasting 3 to 5 years showed a statistically significant 17% reduction in risk of any recurrent colorectal adenomas [RR = 0.83, 95% CI = 0.75-0.93, I2  =  8.5%, p  =  0.36].

The investigators found in the sensitivity analysis of 3 trials with low bias risk a statistically significant 12% reduction in the recurrence of any colorectal adenomas [RR = 0.88, 95% CI = 0.79-0.99, I2  =  0%, p  =  0.54] in patients who were administered supplemental calcium versus placebo.

The investigators found no association between supplemental calcium and recurrence of advanced colorectal adenomas in trials with low risk of bias [RR = 1.02, 95% CI = 0.67-1.55, I2 =  17.5%].

The investigators found in the subgroup analysis of 3 trials with elemental calcium dose ≤ 1200 mg/day, a statistically significant 16% reduction in the recurrent of any colorectal adenomas [RR = 0.84, 95% CI = 0.73-0.97, I2  =  38.5%, p  = 0 .19].

However, a greater reduction of 26% [RR = 0.74, 95% CI = 0.56-0.97, I2  =  0%, p  = 0 .70] was observed in the subgroup analysis of 2 trials with elemental calcium dose ≥ 1600 mg/day.
Subgroup analyses demonstrated no statistically significant association with the reduction of advanced colorectal adenomas in any doses.

The investigators concluded the available good quality RCTs suggests a possible beneficial effect of calcium supplementation – preferably at least 1600 mg/day elemental calcium – on the recurrence of colorectal adenomas. However, TSA indicated that the accumulated evidence is still inconclusive. Therefore, large well-designed randomized trials with low risk of bias are needed.

Original title:
Effects of calcium on the incidence of recurrent colorectal adenomas: A systematic review with meta-analysis and trial sequential analysis of randomized controlled trials by Veettil SK, Ching SM, […], Chaiyakunapruk N.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5556213/

Additional information of El Mondo:
Find more information/studies on calcium and colorectal cancer right here.

Colorectal adenomas can lead to colorectal cancer.

Objectives:
Does a vegetarian diet reduce diabetes risk?

Study design:
This review article included 2 cohort studies and 12 cross-sectional studies.

Although the funnel plot showed a slight asymmetry, publication bias was not detected based on statistical tests such as the Egger’s [p = 0.465] and Begg’s tests [p = 0.584].

Results and conclusions:
The investigators found vegetarians had a 27.4% lower risk of having diabetes than omnivores [OR = 0.726, 95% CI = 0.608-0.867].

The investigators found in the subgroup analyses by sex, study design, region of study and vegetarian type, the pooled OR of all subtotal estimates suggested that vegetarians had a lower prevalence or incidence of diabetes than omnivores. Vegetarian men were less likely to have diabetes than their omnivorous counterparts; in contrast, no such significant association was found in women.

The investigators found in the subgroup analysis, the inverse association between a vegetarian diet and diabetes incidence/prevalence tended to be stronger for the 3 studies conducted in the Western Pacific region [OR = 0.514, 95% CI = 0.304-0.871] and the 7 studies performed in Europe & North America [OR = 0.756, 95% CI = 0.589-0.971] than for the 4 studies conducted in Southeast Asia [OR = 0.888, 95% CI = 0.718-1.099].

The investigators found in the subgroup analysis by types of vegetarianism, most types (vegan, lacto- and lacto-ovo-vegetarians) were significantly associated with a lower prevalence or incidence of diabetes than omnivorous participants, except for pesco-vegetarians.

The investigators found the influence analysis showed that the pooled OR was not dramatically changed when it was recalculated after dropping one study at a time. In other words, no one study had a substantial impact on the pooled effect size; this is indicative of a statistically robust result.

The investigators concluded that a vegetarian diet has a protective effect against diabetes risk. However, well-designed prospective cohort studies from various countries that obtain information on the participants’ motivations for vegetarianism, the duration of adherence to a vegetarian diet and verification of a vegetarian diet are needed to strengthen these findings.

Original title:
Adherence to a Vegetarian Diet and Diabetes Risk: A Systematic Review and Meta-Analysis of Observational Studies by Lee Y and Park K.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5490582/

Additional information of El Mondo:
Find more information/studies on vegetarianism and diabetes right here.

Objectives:
Although epidemiological studies have examined the role of chocolate in preventing cardiometabolic disease, the results remain inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does chocolate consumption reduce risk of coronary heart disease (CHD), stroke and diabetes?

Study design:
This review article included 14 prospective cohort studies, with 508,705 participants from six countries and 7,267 coronary heart disease (CHD) cases, 8,197 stroke cases and 13,271 diabetes cases.
The follow-up duration of the studies ranged from 5 to 16 years.
One serving was defined as 30g of chocolate.
The majority of chocolate consumed in the included studies was milk or dark chocolate.

Results and conclusions:
The investigators found in 6 cohort studies for the highest versus lowest intake of chocolate a significant reduced risk of 10% for coronary heart disease [pooled RR = 0.90, 95% CI = 0.82-0.97, I2 = 24.3%, p = 0.25]. Leave-one-out sensitivity analysis had no significant influence on the pooled results.

The investigators found regarding CHD subtype, a significant reduced risk of 14% [RR = 0.86, 95% CI = 0.77-0.96] for myocardial infarction.

The investigators found for studies with follow-up duration of 10 years a significant reduced risk of 28% for coronary heart disease [RR = 0.72, 95% CI = 0.57-0.92].

The investigators found for studies with follow-up duration of ≥10 years a significant reduced risk of 8% for coronary heart disease [RR = 0.92, 95% CI = 0.86-0.99].

The investigators found in dose-response meta-analysis of 5 studies a curvilinear association between chocolate consumption and risk of coronary heart disease [p for nonlinearity = 0.006].

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 6% for coronary heart disease for 1 serving (30g) chocolate per week [RR = 0.94, 95 CI = 0.90-0.99].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 9% for coronary heart disease for 3 servings (90g) chocolate per week [RR = 0.91, 95 CI = 0.85-0.97].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 11% for coronary heart disease for 7 servings (210g) chocolate per week [RR = 0.89, 95 CI = 0.83-0.95].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 12% for coronary heart disease for 10 servings (300g) chocolate per week [RR = 0.88, 95 CI = 0.81-0.95].   

The investigators found in 8 reports from 7 studies for the highest versus lowest level of chocolate consumption a significant reduced risk of 16% for stroke [pooled RR = 0.84, 95% CI = 0.78-0.90, I2 = 0%, p = 0.49]. The pooled risk of total stroke was not obviously modified in the sensitivity analysis by excluding one study at a time
Egger’s test suggested the presence of publication bias [p = 0.008]. However, after introducing the “trim and fill” method to adjust this bias, the overall risk estimate remained significant in favor of chocolate intake [RR = 0.86, 95% CI = 0.79-0.92].

The investigators found with regard to stroke subtypes, a significant reduced risk of 13% [RR = 0.87, 95% CI = 0.78-0.96] for cerebral infarction and a significant reduced risk of 17% [RR = 0.83, 95% CI = 0.71-0.97] for hemorrhagic stroke.

The investigators found in the stratified analysis by gender, a significant reduced risk of 13% of total stroke for male [RR = 0.87, 95% CI = 0.79-0.97] and a significant reduced risk of 16% of total stroke for female [RR = 0.84, 95% CI = 0.74-0.94].

The investigators found a significant reduced risk of 44% for studies with follow-up durations of 10 years [RR = 0.56, 95% CI = 0.37-0.85].

The investigators found a significant reduced risk of 15% for studies with follow-up durations of ≥10 years [RR = 0.85, 95% CI = 0.79-0.91].

The investigators found in 7 reports from 6 studies a nonlinear correlation between chocolate intake and risk of stroke [p for nonlinearity = 0.001].

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 9% for stroke for 1 serving chocolate per week [RR = 0.91, 95% CI = 0.86-0.97].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 13% for stroke for 3 servings chocolate per week [RR = 0.87, 95% CI = 0.81-0.94].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 15% for stroke for 7 servings chocolate per week [RR = 0.85, 95% CI = 0.76-0.93].   

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 17% for stroke for 10 servings chocolate per week [RR = 0.83, 95% CI = 0.72-0.94].   

The investigators found in 4 studies using “trim and fill” method, for the highest versus lowest intake of chocolate, a non-significant reduced risk of 8% for diabetes [pooled RR = 0.92, 95% CI = 0.78-1.08].

The investigators found in stratified analysis by sex, a significant reduced risk of 21% [RR = 0.79, 95% CI = 0.65-0.96] for men and a non-significant reduced risk of 8% [RR = 0.92, 95% CI = 0.72-1.17] for women.
Similarly, the risks of diabetes were not different between subsets of studies with follow-up durations of below or over 10 years [p for interaction = 0.51].

The investigators found in dose-response meta-analysis of 6 reports, a curvilinear association between chocolate intake and risk of diabetes [p for nonlinearity 0.001].

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 20% for diabetes for 1 serving chocolate per week [RR = 0.80, 95% CI = 0.71-0.91]. Significant means that there is an association with a 95% confidence.

The investigators found in dose-response meta-analysis, compared with no intake, a significant reduced risk of 24% for diabetes for 3 servings chocolate per week [RR = 0.76, 95% CI = 0.63-0.91]. Significant because RR of 1 was not found in the 95% CI of 0.63 to 0.91. RR of 1 means no risk/association.

The investigators found in dose-response meta-analysis, compared with no intake, a non-significant reduced risk of 17% for diabetes for 7 servings chocolate per week [RR = 0.83, 95% CI = 0.67-1.03]. Non-significant means it cannot be said with a 95% confidence that 7 servings chocolate per week really decreased the risk of diabetes with 17%.

The investigators found in dose-response meta-analysis, compared with no intake, a non-significant reduced risk of 11% for diabetes for 10 servings chocolate per week [RR = 0.89, 95% CI = 0.69-1.16].   

The investigators found in general, the dose-response pattern was J-shaped and the peak reduction in diabetes risk occurred at an intake of 2 servings/week [RR = 0.75, 95% CI = 0.63-0.89], with no protective effects observed when consuming chocolate > 6 servings/week.

The investigators concluded that chocolate consumption confers reduced risks of coronary heart disease, stroke and diabetes. Consuming chocolate in moderation (1-6 servings/week or 30-180g) may be optimal for the prevention of these burdensome diseases. However, additional large prospective studies are required to confirm the observed benefits of chocolate in populations with different characteristics and to establish the optimum frequency of chocolate intake for preventing cardiometabolic disease.

Original title:
Chocolate Consumption and Risk of Coronary Heart Disease, Stroke, and Diabetes: A Meta-Analysis of Prospective Studies by Yuan S, Li X, […], Lu J.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537803/

Additional information of El Mondo:
Find more information/studies on chocolate, diabetes and cardiovascular diseases right here.

Objectives:
With only 5-10% of breast cancer cases attributed to genetic inheritance, prevention efforts have focused on modifiable risk factors. Physical activity plays a role in reducing breast cancer risk; however, the interaction between physical activity and other modifiable risk factors, such as obesity, has received little attention. Therefore, this review article (meta-analysis) has been conducted.

What is the relationship between physical activity and breast cancer and how it may be modified by body mass index (BMI)?

Study design:
This review article included 18 cohort and 11 case-control studies.

Results and conclusions:
The investigators found overall, a significant reduction of 15% for breast cancer risk in postmenopausal women with a BMI 25 kg/m² for high versus low levels of physical activity [RR = 0.85, 95% CI = 0.79-0.92]. 

The investigators found overall, a significant reduction of 13% for breast cancer risk in postmenopausal women with a BMI ≥25 kg/m² for high versus low levels of physical activity for women [RR = 0.87, 95% CI = 0.81-0.93]. 

The investigators found overall, a non-significant reduction of 7% for breast cancer risk in postmenopausal women with a BMI ≥30 kg/m² for high versus low levels of physical activity for women [RR = 0.93, 95% CI = 0.76-1.13]. 

The investigators found, however, physical activity was not associated with a significant reduction in risk of breast cancer in premenopausal women in any BMI group.

The investigators concluded high levels of physical activity reduce risk of breast cancer in postmenopausal women with a BMI until 30. Since the included studies used diverse methods for assessment of physical activity and categories of BMI, results should be interpreted with caution and additional work is needed.

Original title:
Does obesity modify the relationship between physical activity and breast cancer risk? by Neil-Sztramko SE, Boyle T, […], Campbell KL.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28803384

Additional information of El Mondo:
Find more information/studies on breast cancer, BMI and physical activity right here.

Objectives:
Does higher protein intake increase bone mineral density?

Study design:
This review article included 6 RCTs and 20 prospective cohort studies.
There were no adverse effects of higher protein intakes.
Studies were heterogeneous and confounding could not be excluded.

Results and conclusions:
The investigators found moderate evidence suggested that higher protein intake may have a protective effect on lumbar spine bone mineral density compared with lower protein intake [net percentage change = 0.52%, 95% CI = 0.06%-0.97%, I2 = 0%, n = 5] but had no effect on total hip, femoral neck, or total body bone mineral density or bone biomarkers.

The investigators concluded that higher protein intake may have a protective effect on lumbar spine bone mineral density. May have because studies were heterogeneous and confounding could not be excluded. Therefore, high-quality, long-term studies are needed to clarify dietary protein's role in bone health.

Original title:
Dietary protein and bone health: a systematic review and meta-analysis from the National Osteoporosis Foundation by Shams-White MM, Chung M, […], Weaver CM.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28404575

Additional information of El Mondo:
Find more information/studies on protein and elderly right here.

A higher protein diet is a diet with 20-35 En% protein. The easiest way to meet a diet with 20-35 En% protein is to choose food items/meals with also 20-35 En% protein. Check here which products contain 20-35 En% protein.
 

Objectives:
Adequate nutrition is critical for optimal growth and development. However, young children may be at risk of nutrient deficiencies when transitioning to weaning foods for a variety of reasons. Supplementation with fortified milk may provide potentially lacking essential nutrients, but effects on growth and nutritional status are yet to be established. Therefore, this meta-analysis (review article) has been conducted.

Have fortified milk beneficial effects on growth and nutritional outcomes in young children?

Study design:
This review article included 15 RCTs with healthy children aged 6-47 months. Fortification varied from iron, zinc, vitamins, essential fatty acids, to pre- and/or probiotics.
Frequently reported outcomes were weight, height and iron status.
Studies varied in geographical location, sample size and duration.

Results and conclusions:
The investigators found that fortified milk had minimal effects on weight gain [mean difference = 0.17 kg, 95% CI = 0.02 to 0.31 kg] compared with control milk.

The investigators found a significant reduced risk of 68% [OR = 0.32, 95% CI = 0.15 to 0.66] for anaemia in fortified milk group compared with control group.

The investigators found no significant effects on height gain, changes in body composition or haemoglobin concentration.

The investigators concluded that fortified milk is an effective source of complementary nutrition to supplement children in need when consumed in appropriate amounts in addition to a normal diet. Due to compositional differences, further research on fortified milk is warranted before making global recommendations on benefits for growth and nutritional outcomes in young children.

Original title:
Effect of fortified milk on growth and nutritional status in young children: a systematic review and meta-analysis by Matsuyama M, Harb T, […], Hill RJ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27938461

Additional information of El Mondo:
Find more information/studies on food fortification/malnutrition right here.
 

Objectives:
The association between vitamin D deficiency and early spontaneous pregnancy loss (SPL) is unclear. Therefore, this review article (meta-analysis) has been conducted.

Does a vitamin D deficiency increase risk of early spontaneous pregnancy loss?

Study design:
This review article included 5 studies (case-control and cohort studies), including 10,630 pregnant women.

Results and conclusions:
The investigators found no significant association between a low 25(OH)D level (vitamin D level in blood) and an increased risk of early spontaneous pregnancy loss.

However, the investigators found in subgroup analysis, an extremely low 25(OH)D level (20 ng/mL) was significantly associated with an 124% increased risk of early spontaneous pregnancy loss in the first trimester [relative risk = 2.24, 95% CI = 1.15-4.37, I2 = 0.0%, p = 0.355].

The investigators concluded that severe vitamin D deficiency (20 ng/mL) could be detrimental to early embryonic development and increases risk of early spontaneous pregnancy loss.

Original title:
Meta-analysis of the effect of the maternal vitamin D level on the risk of spontaneous pregnancy loss by Zhang H, Huang Z, [...], Wei Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28500757

Additional information of El Mondo:
Find more information/studies on vitamin D, pregnancy and review article/significant/95% CI right here.

Objectives:
Does resistance training reduce blood pressure in prehypertensive and hypertensive subjects?

Study design:
This review article included 5 RCTs provided data on 201 individuals.

Results and conclusions:
The investigators found when compared to group control, resistance training alone significantly reduced systolic blood pressure with 8.2 mmHg in prehypertensive and hypertensive subjects [95% CI = -10.9 to -5.5, I2 = 22.5%, p for heterogeneity = 0.271 and effect size = -0.97].

The investigators found when compared to group control, resistance training alone significantly reduced diastolic blood pressure with 4.1 mmHg in prehypertensive and hypertensive subjects [95% CI = -6.3 to -1.9, I2 = 46.5%, p for heterogeneity = 0.113 and effect size = -0.60].

The investigators concluded resistance training alone reduces systolic and diastolic blood pressure in prehypertensive and hypertensive subjects. These findings support the recommendation of resistance training as a tool for management of systemic hypertension.

Original title:
Resistance training alone reduces systolic and diastolic blood pressure in prehypertensive and hypertensive individuals: meta-analysis by de Sousa EC, Abrahin O, […], Vieira RP.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28769100

Additional information of El Mondo:
Find more information/studies on sport nutrition and lowering blood pressure right here.

Objectives:
In the 2007 World Cancer Research Fund/American Institute for Cancer Research Second Expert Report, the expert panel judged that there was strong evidence that alcoholic drinks and body fatness increased esophageal cancer risk, whereas fruits and vegetables probably decreased its risk. The judgments were mainly based on case-control studies. As part of the Continuous Update Project (CUP), this review article (meta-analysis) has been conducted.

What is the relationship between nutrition and esophageal cancer risk?

Study design:
This review article included a total of 57 cohort studies, used in previous 13 meta-analyses.

Results and conclusions:
The investigators found a significant reduced risk of 11% for esophageal adenocarcinoma for every increment of 100g/day vegetable intake [RR = 0.89, 95% CI = 0.80-0.99, n = 3].

The investigators found a significant increased risk of 47% for esophageal adenocarcinoma for every 5 unit increment in BMI [RR = 1.47, 95% CI = 1.34-1.61, n = 9].

The investigators found a significant reduced risk of 16% for esophageal squamous cell carcinoma for every increment of 100g/day fruit intake [RR = 0.84, 95% CI = 0.75-0.94, n = 3].

The investigators found a significant reduced risk of 36% for esophageal squamous cell carcinoma for every 5 unit increment in BMI [RR = 0.64, 95% CI = 0.56-0.73, n = 8].

The investigators found a significant increased risk of 59% for esophageal squamous cell carcinoma for every increment of 50g/day processed meat intake [RR = 1.59, 95% CI = 1.11-2.28, n = 3].

The investigators found a significant increased risk of 37% for esophageal squamous cell carcinoma for every increment of 100g/day processed and red meat intake [RR = 1.37, 95% CI = 1.04-1.82, n = 3].

The investigators found a significant increased risk of 25% for esophageal squamous cell carcinoma for every increment of 10g/day alcohol intake [RR = 1.25, 95% CI = 1.12-1.41, n = 6].

The investigators concluded evidence from cohort studies shows a protective role of vegetables and body weight control in esophageal adenocarcinomas development. For squamous cell carcinomas, higher intakes of red and processed meats and alcohol increase the risk, whereas fruits intake has a protective role.

Original title:
An update of the WCRF/AICR systematic literature review and meta-analysis on dietary and anthropometric factors and esophageal cancer risk by Vingeliene S, Chan DSM, […], Norat T.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28666313

Additional information of El Mondo:
Find more information/studies on vegetable, fruit, alcohol and meat consumption, significant/cohort/95% CI and cancer right here.
 

Objectives:
Are there differences in serum ceruloplasmin levels between patients with preeclampsia and healthy controls?

Study design:
This review article included 15 studies, with a total number of 1927 women.

Results and conclusions:
The investigators found that maternal serum ceruloplasmin concentration was significantly higher in preeclamptic than in the healthy pregnant women [MD = 12.57 mg/dL, 95% CI = 8.81 to 16.33].

The investigators found that ceruloplasmin levels were significantly higher both in mild [MD = 13.8 mg/dL, 95% CI = 2.64 to 23.53] and severe [MD = 21.84 mg/dL, 95% CI = 0.97 to 42.71] preeclampsia, when compared to the control group.

The investigators found that the severity of the disease did not significantly affect the levels of protein [MD = -9.34 mg/dL, 95% CI = -20.93 to 2.26].

The investigators concluded that serum ceruloplasmin may be a useful screening and follow-up tool for the evaluation of pregnant women with an indicative history of developing preeclampsia. Future studies are needed to evaluate the levels of this specific protein throughout the pregnancy course and provide data on its sensitivity and specificity by introducing cut-off values.

Original title:
Serum ceruloplasmin levels in preeclampsia: a meta-analysis by Bellos I, Papantoniou N and Pergialiotis V.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28605950

Additional information of El Mondo:
Find more information/studies on copper, pregnancy and review article/significant/95% CI right here.

Ceruloplasmin carries 65% to 90% of the copper found in blood.

Objectives:
Promising experimental studies suggest that quercetin has potential anti-inflammatory effects. However, the results of current clinical trials on quercetin's effects on the C-reactive protein (CRP), a sensitive inflammatory biomarker, are ambiguous. Therefore, this review article (meta-analysis) has been conducted.

Does quercetin supplementation reduce CRP levels?

Study design:
This review article included 7 RCTs with 10 treatment arms.

Results and conclusions:
The investigators found a significant reduction of circulating CRP levels [WMD = -0.33 mg/L, 95% CI = -0.50 to -0.15, p 0.001] following quercetin supplementation.

The investigators found in subgroup analysis, a significant reducing effect in trials with ≥500 mg/day dosage [WMD = -0.34 mg/L, 95% CI = -0.52 to -0.16, p ≤ 0.001] and in those with CRP 3 mg/L [WMD = -0.34 mg/L, 95% CI = -0.51 to -0.18, p ≤ 0.001].

The investigators found in meta-regression, no association between changes in CRP concentrations, dose of supplementation and CRP baseline values.

The investigators concluded quercetin supplementation reduces circulating C-reactive protein levels; especially at doses above 500 mg/day and in patients with CRP 3 mg/L.
 
Original title:
Effects of supplementation with quercetin on plasma C-reactive protein concentrations: a systematic review and meta-analysis of randomized controlled trials by Mohammadi-Sartang M, Mazloom Z, […], Firoozi D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28537580

Additional information of El Mondo:
Find more information/studies on chronic disease and flavonoids right here. Quercetin is a flavonoid.

Objectives:
The relationship between intake of fish and n-3 fatty acids and endometrial cancer risk has not been consistent across epidemiological studies. Therefore, this review article (meta-analysis) has been conducted.

Do fish consumption and dietary EPA and DHA intake reduce endometrial cancer risk?

Study design:
This review article included 4 prospective cohort studies, 1 case-cohort study and 11 case-control studies (including 8 population-based case-control studies and 3 hospital-based case-control studies).
The prospective cohort studies had a mean follow-up of 6.5 to 9.1 years.
The highest category of fish ranged from >1-2 servings/week to >15.4 servings/week,
The highest category of DHA ranged from 143 to 227 mg/d.
The highest category of EPA ranged from 74.7 to 127 mg/d.

When fish intake was reported in unit of g/d, it was converted to serving/week by assuming 1 serving = 100g.
Overall, all 16 studies were classified as high-quality studies.
There was no publication bias.

Results and conclusions:
The investigators found a non-significant association between the highest vs. lowest category of fish consumption and endometrial cancer risk [RR = 1.04, 95% CI = 0.84-1.30, I2 = 80.4%].
According to the subgroup analyses, the null association persisted in strata according to study design, location, type of controls, number of cases, publication year and adjustments of energy intake, reproductive factors and smoking.

The investigators found in subgroup analyses for every one additional serving/week of fish intake, a significant reduced risk of 10% for endometrial cancer in studies conducted in Europe [RR = 0.90, 95% CI = 0.84-0.97]. Significant means that there is an association with a 95% confidence.

The investigators found in subgroup analyses for every one additional serving/week of fish intake, a significant increased risk of 15% for endometrial cancer in studies conducted in Asia [RR = 1.15, 95% CI = 1.10-1.21]. Significant because RR of 1 was not found in the 95% CI of 1.10 to 1.21. RR of 1 means no risk/association.

The investigators found in studies adjusting for smoking for every one additional serving/week of fish intake, a significant reduced risk of 5% for endometrial cancer [RR = 0.95, 95% CI = 0.91-1.00].

The investigators found in studies without an adjustment of smoking for every one additional serving/week of fish intake, a significant increased risk of 14% for endometrial cancer [RR = 1.14, 95% CI = 1.09-1.19].

The investigators found a non-significant inverse association between the highest category of DHA intake and endometrial cancer risk [RR = 0.85, 95% CI = 0.64-1.11, I2 = 59.6%]. However, the dose-response analysis suggested a significant non-linear relationship between DHA intake and endometrial cancer risk [p = 0.04 and p for heterogeneity = 0.39], with a decreased risk being detected for an intake of DHA no more than 175 mg/d.

The investigators concluded that there is a significant inverse association between every one additional serving/week of fish intake and endometrial cancer risk in studies conducted in Europe and studies adjusted for smoking. Furthermore, there is a significant non-linear relationship between DHA intake and risk of endometrial cancer, with a decreased risk being detected for an intake of DHA no more than 175 mg/d. Further well-designed studies are warranted to better characterize the relationship between fish, n-3 PUFA and endometrial cancer development.

Original title:
Dietary n-3 polyunsaturated fatty acids, fish consumption, and endometrial cancer risk: a meta-analysis of epidemiological studies by Hou R, Yao SS, […], Jiang L.

Link:
http://www.impactjournals.com/oncotarget/index.php?journal=oncotarget&page=article&op=view&path[]=18295&path[]=58664

Additional information of El Mondo:
Find more information/studies on fish consumption, significant/cohort/95% CI and cancer right here.
These fish contain 175 mg DHA.
 

Objectives:
The associations between n-3 polyunsaturated fatty acids (PUFAs) and metabolic syndrome (MetS) risk have demonstrated inconsistent results. Therefore, this review article (meta-analysis) has been conducted.

Do higher circulating n-3 PUFA levels associate with a lower metabolic syndrome risk?

Study design:
This review article included a total of 7 case-control studies and 20 cross-sectional studies.
There was no publication bias.
Results and conclusions:
The investigators found a higher plasma/serum n-3 PUFAs was associated with a lower metabolic syndrome risk of 37% [pooled OR = 0.63, 95% CI = 0.49-0.81, I2 = 72.4%].

The investigators found the plasma/serum n-3 PUFAs in controls was significantly higher than cases [WMD = 0.24, 95% CI = 0.04-0.43], especially docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA).

The investigators found, however, no significant association between dietary intake of n-3 PUFAs or fish and metabolic syndrome risk.

The investigators found in sensitivity analysis by omitting one study at a time and re-calculated the remaining data, that exclusion of anyone study did not substantially influence the pooled effects.

The investigators concluded a higher circulating n-3 PUFAs is associated with a lower metabolic syndrome risk. The circulating n-3 PUFAs can be regarded as biomarkers indicating metabolic syndrome risk, especially DPA and DHA. The evidence of this review article will have important public implications in preventing metabolic syndrome through supplemental long-chain n-3 PUFAs of marine-origin. Furthermore, added RCTs and epidemiological studies with large sample-size are warranted to confirm these findings.

Original title:
n-3 Polyunsaturated Fatty Acids and Metabolic Syndrome Risk: A Meta-Analysis by Guo XF, Li X, […], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537818/

Additional information of El Mondo:
Find more information/studies on overweight and n-3 PUFA right here.  
Docosapentaenoic acid (DPA) is a dietary omega-3 fatty acid mainly found in fish, fish oil, seal oil and red meat.

Find out whether you are overweight or not right here.

Objectives:
Have flaxseed supplementation positive effects on body composition?

Study design:
This review article included a total of 45 RCTs.

Results and conclusions:
The investigators found a significant reduction in body weight [WMD = -0.99 kg, 95% CI = -1.67 to -0.31, p = 0.004], BMI [WMD = -0.30 kg m², 95% CI = -0.53 to -0.08, p = 0.008] and waist circumference [WMD = -0.80 cm, 95% CI = -1.40 to -0.20, p = 0.008] following flaxseed supplementation.

The investigators found subgroup analyses showed that using whole flaxseed in doses ≥30 g/d, longer-term interventions (≥12 weeks) and studies including participants with higher BMI (≥ 27 kg/m²) had positive effects on body composition.

The investigators concluded whole flaxseed supplementation in doses ≥30 g/d during ≥12 weeks has positive effects on body composition in overweight and obese participants (=participants with BMI ≥ 25 kg/m²).

Original title:
The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta-analysis of 45 randomized placebo-controlled trials by Mohammadi-Sartang M, Mazloom Z, […], Totosy de Zepetnek JO.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28635182

Additional information of El Mondo:
Find more information/studies on overweight right here. 

Find out whether you are overweight or not right here.

Objectives:
Although several epidemiological studies have investigated the association between dietary calcium intake and the risk of esophageal cancer, the results are inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does dietary calcium intake reduce risk of esophageal cancer?

Study design:
This review article included 3 cohort studies and 14 case-control studies, including 3,396 cases (subjects with esophageal cancer) and 346,815 controls (subjects without esophageal cancer).

Egger’s test showed no evidence of significant publication bias.

The sample size was large enough to evaluate the effect of calcium intake on esophageal cancer.

A dose-response effect analysis could not be performed due to the incomplete data of dietary calcium intake.

The average of highest dietary calcium intake in Asian populations was 621 mg/day.

Results and conclusions:
The investigators found for highest vs. lowest dietary calcium intake a significant reduced risk of 20% for esophageal cancer [pooled OR = 0.80, 95% CI = 0.71-0.91, I2 = 33.6%].
This significant reduced risk was also found in studies conducted in Asia [OR = 0.67, 95% CI = 0.52-0.86, I2 = 0.0%], studies published after 2000 [OR = 0.64, 95% CI = 0.53-0.77, I2 = 0.0%), studies adjusted for dietary energy intake [OR = 0.83, 95% CI = 0.70-0.98, I2 = 3.6%], studies of esophageal squamous cell carcinoma [OR = 0.76, 95% CI = 0.60-0.96, I2 = 28.3%], cohort studies [OR = 0.67, 95% CI = 0.54-0.84, I2 = 23.6%] and studies with high quality score [OR = 0.76, 95% CI = 0.66-0.87, I2 = 12.7%].

The investigators found in sensitivity analysis (conducted by leaving one study out in turn and pooling the ORs of the remaining studies) the summary ORs did not substantially change, which indicated that the results were statistically robust.

The investigators concluded that a higher intake (621 mg/day) of dietary calcium has protective effect against esophageal cancer - especially esophageal squamous cell cancer - in Asian populations. To further solidify the association of dietary calcium intake with the risk of esophageal cancer, well-designed studies - especially prospective cohort studies with validated FFQ and adjusted for dietary energy intake - should be conducted.

Original title:
Protective Effect of Dietary Calcium Intake on Esophageal Cancer Risk: A Meta-Analysis of Observational Studies by Li Q, Cui, L, […], Wang L.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452240/

Additional information of El Mondo:
Find more information/studies on calcium, significant/cohort/95% CI and cancer right here.
 

Objectives:
Previous studies have demonstrated that asthma might be associated with an increase in cardiovascular disease (CVD) and death. However, this relationship differs by gender. Therefore, this review article (meta-analysis) has been conducted.

Is asthma associate with an increase risk in cardiovascular disease and death among men and women?

Study design:
This review article included 4 retrospective cohort studies and 6 prospective cohort studies. The length of follow-up ranged from 4.5 to 27 years. The sample sizes of the cohorts ranged from 1,233 to 151,620 (a total of 406,426).

There was no evidence of publication bias [Begg’s, p = 1.000 and Egger’s linear regression, p = 0.150].

Results and conclusions:
The investigators found overall, subjects with asthma experienced a significant increased risk of 33% for cardiovascular disease events [RR = 1.33, 95% CI = 1.15-1.53, p 0.0001, I2 = 88%, p 0.00001]. These findings remained consistent after sensitivity analysis by omitting one study each time.

The investigators found in subgroup analyses that women with asthma had a significantly higher risk of cardiovascular disease as compared to the reference group [RR = 1.55, 95% CI = 1.20-2.00, p = 0.0007, I2 = 84%], whereas no significant association was found in men [RR = 1.20, I2 = 83%, 95% CI = 0.92-1.56, p = 0.17]. However, the combined RR value was 1.36, 95% CI = 1.15-1.62, p = 0.0003]. These findings remained consistent after sensitivity analysis by omitting one study each time.
To further explore the interaction between gender and asthma on cardiovascular disease risk, the “test for subgroup differences” were examined and gave a p = 0.17, which suggested that the influence of gender on the association between asthma and cardiovascular disease risk was not statistically significant. Therefore, it cannot confirm or refute a significant difference in the incidence of cardiovascular disease between male and female asthmatic patients.

The investigators found asthma was associated with an increased risk of 36% of all-cause mortality in a random effects model as compared to reference subjects without asthma [RR = 1.36, 95% CI = 1.01-1.83, p = 0.05, I2 = 62%, p = 0.05]. These findings remained consistent after sensitivity analysis by omitting one study each time.

The investigators concluded there is an association between asthma and an increased risk of cardiovascular disease and all-cause mortality and women with asthma have a higher risk of cardiovascular disease than men with asthma. These findings indicate a need for early detection and intervention during general outpatient visits in asthmatics who may have potential cardiovascular disease complications or mortality.

Original title:
Asthma and risk of cardiovascular disease or all-cause mortality: a meta-analysis by Xu M, Xu J and Yang X.

Link:
http://www.annsaudimed.net/index.php/vol37/vol37iss2/1109.html

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