Nutritional advice

Objectives:
Fish oil supplementation has been shown to be associated with a lower risk of metabolic syndrome and benefit a wide range of chronic diseases, such as cardiovascular disease, type 2 diabetes and several types of cancers. However, the evidence of fish oil supplementation on glucose metabolism and insulin sensitivity is still controversial. Therefore, this review article (meta-analysis) has been conducted.

Does fish oil supplementation improve insulin sensitivity in humans?

Study design:
This review article included a total of 17 RCTs with 672 participants. One of the 17 studies was crossover design and others were parallel design.
The doses of active ingredients of fish oil (n-3 fatty acids) ranged from 1 g/d to 4 g/d. Duration of the interventions was ranged from 4 weeks to 24 weeks.
There was no suggestion of small study effect based on visual inspection of the funnel plot. Results of the Egger’s (p = 0.78) and Begg’s (p = 0.43) tests showed that there was no potential publication bias.

Results and conclusions:
The investigators found pooled analysis showed that fish oil supplementation had no effects on insulin sensitivity overall [SMD = 0.17, 95% CI = -0.15 to 0.48, p = 0.292, I2 = 58.1%, p = 0.001].

The investigators found subgroup analysis showed that fish oil supplementation significantly improved insulin sensitivity among people who were experiencing at least one symptom of metabolic disorders [SMD = 0.53, 95% CI = 0.17 to 0.88, p 0.001].

The investigators found subgroup analysis showed a positive effect of fish oil on insulin sensitivity among the short-term intervention group (12 weeks) rather than the long-term intervention group [SMD = 0.31, 95% CI = 0.01-0.61, p = 0.04].

The investigators found subgroup analysis showed that fish oil had no effects on insulin sensitivity among the healthy people or people with T2DM.

The investigators found there were no significant differences between subgroups of methods of insulin sensitivity and doses of omega-3 polyunsaturated fatty acids (n-3 PUFA) of fish oil supplementation.

The investigators found in sensitivity analysis that summary results did not differ significantly when omitting studies one at a time.

The investigators concluded that fish oil supplementation during 12 weeks improves insulin sensitivity among people who were experiencing at least one symptom of metabolic disorders.

Original title:
Fish oil supplementation and insulin sensitivity: a systematic review and meta-analysis by Gao H, Geng T, [...], Zhao Q.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5496233/

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

 

Objectives:
Women have a 50% risk of urinary tract infection (UTI) over their lifetime and 20-30% experience a subsequent urinary tract infection recurrence. Cranberry (Vaccinium spp.) has been advocated for treatment of urinary tract infection; however, its efficacy is controversial. Therefore, this review article (meta-analysis) has been conducted.

Does cranberry reduce the risk of urinary tract infection recurrence in healthy women?

Study design:
This review article included 7 RCTs conducted in healthy nonpregnant women aged ≥18 years with a history of urinary tract infection (n = 1498 participants).
Risk of bias indicated that 2 studies had high loss to follow-up or selective outcome reporting. Overall, the studies were relatively small, with only 2 having >300 participants.

Results and conclusions:
The investigators found that cranberry significantly reduced the risk of urinary tract infection by 26% [pooled risk ratio = 0.74, 95% CI = 0.55-0.98, I2 = 54%].

The investigators concluded that cranberry may be effective in preventing urinary tract infection recurrence in generally healthy women. May be effective because the studies were relatively small, with only 2 having >300 participants. Therefore, larger high-quality studies are needed to confirm these findings.

Original title:
Cranberry Reduces the Risk of Urinary Tract Infection Recurrence in Otherwise Healthy Women: A Systematic Review and Meta-Analysis by Zhuxuan Fu, DeAnn Liska, […], Mei Chung.

Link:
http://jn.nutrition.org/content/147/12/2282.abstract

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

Objectives:
Epidemiological studies have provided controversial evidence between beverage consumption and the risk of ulcerative colitis (UC). Therefore, this review article (meta-analysis) has been conducted.

Is there a relationship between beverage consumption and risk of ulcerative colitis?

Study design:
This review article included 13 case-control studies and 3 prospective cohort studies, with a total of 3,689 cases (subjects with ulcerative colitis) and 335,339 controls (subjects without ulcerative colitis).

Egger test detected no significant publication bias.

Results and conclusions:
The investigators found high intake of soft drinks versus low intake, significantly increased risk of ulcerative colitis with 69% [pooled RR = 1.69, 95% CI = 1.24-2.30, I2  =  12.9%, p  = 0 .332].
In subgroup analysis, no substantial changes of the primary result were found between subgroups.

The investigators found high tea consumption versus low consumption, significantly decreased risk of ulcerative colitis with 31% [pooled RR = 0.69, 95% CI = 0.58-0.83, I2  =  0.0%, p  = 0 .697].
In subgroup analysis, no substantial changes of the primary result were found between subgroups.

The investigators found no significant association between alcohol [pooled RR = 1.08, 95% CI = 0.66-1.51] or coffee consumption [pooled RR = 0.58, 95% CI = 0.33-1.05, I2  =  87.5%, p    0.001] and risk of ulcerative colitis. No significant association because RR of 1 was found in the 95% CI of 0.66 to 1.51. RR of 1 means no risk/association.

The investigators concluded high consumption of soft drinks increases the risk of ulcerative colitis, while high tea consumption decreases the risk.

Original title:
Beverage consumption and risk of ulcerative colitis. Systematic review and meta-analysis of epidemiological studies by Nie JY and Zhao Q.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5728934/

Additional information of El Mondo:
Find more information/studies on chronic disease, alcohol and tea consumption right here.
 

Objectives:
The role of omega-3 polyunsaturated fatty acids (omega-3 or n-3 PUFAs) in the pathogenesis and treatment of children and adolescents with attention deficit hyperactivity disorder (ADHD) is unclear. Therefore, this review article (meta-analysis) has been conducted.

Do children and adolescents with attention deficit hyperactivity disorder (ADHD) benefit from n-3 PUFA supplementation?

Study design:
This review article included 7 RCTs and 7 case-control studies.

Results and conclusions:
The investigators found in 7 RCTs (n = 534 randomised youth with ADHD) n-3 PUFAs supplementation significantly improved ADHD clinical symptom scores [g = 0.38, p 0.0001].

The investigators found in 3 RCTs (n = 214 randomised youth with ADHD) n-3 PUFAs supplementation significantly improved cognitive measures associated with attention [g = 1.09, p = 0.001].

The investigators found children and adolescents with ADHD had lower levels of DHA [7 case-control studies, n = 412, g = -0.76, p = 0.0002], EPA (7 case-control studies, n = 468, g = -0.38, p = 0.0008] and total n-3 PUFAs [6 case-control studies, n = 396, g = -0.58, p = 0.0001].

The investigators concluded there is evidence that n-3 PUFAs supplementation monotherapy improves clinical symptoms and cognitive performances in children and adolescents with ADHD and that these youth have a deficiency in n-3 PUFAs levels. These findings provide further support to the rationale for using n-3 PUFAs as a treatment option for ADHD.

Original title:
Omega-3 Polyunsaturated Fatty Acids in Youths with Attention Deficit Hyperactivity Disorder (ADHD): A Systematic Review and Meta-Analysis of Clinical Trials and Biological Studies by Chang JC, Su KP, [...], Pariante CM.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28741625

Additional information of El Mondo:
Find more information/studies on chronic disease, n-3 PUFA right here.
EPA and DHA are n-3 PUFA.

Objectives:
Recent data pose the question whether conservative management of chronic kidney disease (CKD) by means of a low-protein diet can be a safe and effective means to avoid or defer transition to dialysis therapy without causing protein-energy wasting or cachexia. Therefore, this review article (meta-analysis) has been conducted.

Do subjects with chronic kidney disease benefit from a low-protein diet?

Study design:
This review article included 16 controlled trials of low-protein diet in chronic kidney disease that met the stringent qualification criteria including having 30 or more participants.

Results and conclusions:
The investigators found compared with diets with protein intake of >0.8 g/kg/day, diets with restricted protein intake (0.8 g/kg/day) were associated with higher serum bicarbonate levels, lower phosphorus levels, lower azotemia, lower rates of progression to end-stage renal disease and a trend towards lower rates of all-cause death.

The investigators found compared with diets with protein intake of >0.8 g/kg/day, very-low-protein diets (protein intake 0.4 g/kg/day) were associated with greater preservation of kidney function and reduction in the rate of progression to end-stage renal disease.

The investigators found safety and adherence to a low-protein diet was not inferior to a normal protein diet and there was no difference in the rate of malnutrition or protein-energy wasting.

The investigators concluded a low-protein diet, particularly protein intake 0.4 g/kg/day, appears to enhance the conservative management of non-dialysis-dependent chronic kidney disease and may be considered as a potential option for chronic kidney disease patients who wish to avoid or defer dialysis initiation and to slow down the progression of chronic kidney disease, while the risk of protein-energy wasting and cachexia remains minimal.
 
Original title:
Low-protein diet for conservative management of chronic kidney disease: a systematic review and meta-analysis of controlled trials by Rhee CM, Ahmadi SF, [...], Kalantar-Zadeh K.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29094800

Additional information of El Mondo:
Find more information/studies on chronic disease and protein right here.
A protein intake of 0.8 g/kg/day usually corresponds to a diet with 11 En% protein.
A protein intake of 0.4 g/kg/day usually corresponds to a diet with 5.5 En% protein.
A diet with 5.5 En% protein is a diet with a lot of products with 5.5 En% protein. Check here which products contain 5.5 En% protein.
 

Objectives:
The potential glucose-lowering effects of pomegranate have been reported in animal and observational studies, but intervention studies in humans have generated mixed results. Therefore, this review article (meta-analysis) has been conducted.

What are the effects of pomegranate supplementation on measures of glucose control, insulin levels and insulin sensitivity in humans?

Study design:
This review article included 16 RCTs with 538 subjects. 14 trials adopted parallel study designs and the 2 remaining trials used crossover designs.
The total number of subjects included in each study ranged from 14 to 74 subjects.
The mean age of participants in each trial ranged from 30 to 70 years, with differing age ranges in most studies.
11 studies used pomegranate juice as a supplement (the dosage ranged from 120 to 500 ml/day).
2 studies used pomegranate seed oil as treatments (the dosage ranged from 400 to 2000 mg/day).
3 studies utilized pomegranate extract as the intervention (the dosage ranged from 710 to 1420 mg/day).  
The duration of the pomegranate intervention varied from 1 to 12 weeks (median: 5.5 weeks).

Overall, significant heterogeneity was detected for FBI and HOMA-IR, but subgroup analysis could not identify factors significantly influencing these parameters.
No significant publication bias was found.

Results and conclusions:
The investigators found that pomegranate did not significantly affect the measures of:
-FBG (fasting blood glucose) [WMD = -0.6 mg/dL, 95% CI = -2.79 to 1.58, p = 0.59, I2 = 0%];
-FBI (fasting blood insulin) [WMD = 0.29 μIU/mL, 95% CI = -1.16 to 1.75, p = 0.70, I2 = 60.4%];
-HOMA-IR (homeostatic model assessment of insulin resistance) [WMD = -0.04, 95% CI = -0.53 to 0.46, p = 0.88, I2 = 59.8%] or;
-HbA1c (glycated haemoglobin) [WMD = -0.11%, 95% CI = -0.39 to 0.18, p = 0.46, I2 = 0%].
These results were robust in sensitivity analysis.

The investigators found meta-regression analysis showed that the factor (dose of pomegranate juice supplementation) was not associated with the treatment effects on FBG level [coefficient = -0.006, 95% CI = -0.023 to 0.011, p = 0.46].

The investigators found no significant difference in the FBG-lowering effect between trials that were conducted in subjects with cardiovascular disease risk [WMD = 0.30 mg/dL, 95% CI = -2.36 to 2.97, p = 0.82] and those that were conducted in healthy individuals [WMD = -2.53 mg/dL, 95% CI = -6.36 to 1.30, p = 0.19].

The investigators found no statistically significant differences in the pooled effects of pomegranate on FBG in the subgroups stratified by study designs, intervention durations, types of intervention, baseline BMI and baseline FBG levels (FBG levels at the beginning of the studie).

The investigators concluded pomegranate supplements have no favourable effect on improvements in glucose and insulin metabolism. The current evidence suggests that daily pomegranate supplementation is not recommended as a potential therapeutic strategy in glycemic management. Further large-scale RCTs with longer duration are required to confirm these results.

Original title:
Lack of efficacy of pomegranate supplementation for glucose management, insulin levels and sensitivity: evidence from a systematic review and meta-analysis by Huang H, Liao D, […], Zhu Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5629805/

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

Objectives:
Over 200 clinical trials have examined the effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplements on risk factors associated with cardiovascular disease. However, an updated analysis of the evidence is lacking. Therefore, this review article (meta-analysis) has been conducted.

Do EPA and DHA supplements reduce risk of cardiovascular diseases?

Study design:
This review article included 171 RCTs with acceptable quality (Jadad score ≥3).

Results and conclusions:
The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of triglycerides of 0.368 mmol/L [95% CI = -0.427 to -0.309].
The triglyceride-lowering effect was dose-dependent.

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of systolic blood pressure of 2.195 mmHg [95% CI = -3.172 to -1.217].

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of diastolic blood pressure of 1.08 mmHg [95% CI = -1.716 to -0.444].

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of heart rate of 1.37 bpm [95% CI = -2.41 to -0.325].

The investigators found compared to placebo-control, EPA and DHA supplements produced significant reductions of C-reactive protein of 0.343 mg/L [95% CI = -0.454 to -0.232].

The investigators found compared to placebo-control, EPA and DHA supplements produced a significant increase of LDL cholesterol (bad cholesterol) [mean difference = 0.150 mmol/L, 95% CI = 0.058 to 0.243].

The investigators found compared to placebo-control, EPA and DHA supplements produced a significant increase of HDL cholesterol (good cholesterol) [mean difference = 0.039 mmol/L, 95% CI = 0.024-0.054].

The investigators concluded EPA and DHA supplements have lipid-lowering, hypotensive, anti-arrhythmic and anti-inflammatory effects.

Original title:
Eicosapentaenoic acid and docosahexaenoic acid containing supplements modulate risk factors for cardiovascular disease: a meta-analysis of randomised placebo-control human clinical trials by AbuMweis S, Jew S, […], Agraib L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28675488

Additional information of El Mondo:
Find more information/studies on EPA and DHA, cholesterol and cardiovascular diseases right here. 

Objectives:
The results of randomized controlled trials (RCTs) investigating resveratrol supplementation on risk factors of non-communicable diseases (NCDs) have been inconsistent. Therefore, this review article (meta-analysis) has been conducted.

Does resveratrol supplementation reduce risk of non-communicable diseases?

Study design:
This review article included 29 RCTs (30 treatment arms) with 1069 participants.

Results and conclusions:
The investigators found that resveratrol supplementation significantly reduced the concentrations of:
-fasting glucose [-4.77 mg/dL, 95% CI = -9.33 to -0.21 mg/dL, p = 0.040];
-total cholesterol (TC) [-9.75 mg/dL, 95% CI = -17.04 to -2.46 mg/dL, p = 0.009] and;
-C-reactive protein (CRP) [-0.81 mg/L, 95% CI = -1.42 to -0.21 mg/L, p = 0.009].

The investigators found that resveratrol intervention exerted significant reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) in subjects with type 2 diabetes mellitus (T2DM).

The investigators found subgroup analysis also showed that the trials with resveratrol intervention ≥3 months significantly reduced the low-density lipoprotein (LDL) cholesterol (bad cholesterol), diastolic blood pressure and glycated hemoglobin (HbA1c) values.

The investigators found that resveratrol intervention had no favourable effects in altering high-density lipoprotein (HDL) cholesterol (good cholesterol), triglyceride (TAG) and homeostasis model assessment of insulin resistance (HOMA-IR).

The investigators concluded resveratrol supplementation ≥3 months has favourable effects on several risk factors of non-communicable diseases.

Original title:
Effects of resveratrol supplementation on risk factors of non-communicable diseases: A meta-analysis of randomized controlled trials by Guo XF, Li JM, [...], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28933578

Additional information of El Mondo:
Find more information/studies on flavonoids, cholesterol, blood pressure, diabetes and chronic diseases right here.

Non-communicable or chronic diseases are diseases of long duration and generally slow progression. The four main types of non-communicable diseases are cardiovascular diseases (like heart attacks and stroke), cancer, chronic respiratory diseases (such as chronic obstructed pulmonary disease and asthma) and diabetes.

Non-communicable diseases are by far the leading cause of death in the world.
 

Objectives:
Do patients with type 2 diabetes benefit from a low carbohydrate diet?

Study design:
This review article included a total of 9 RCTs with 734 patients with type 2 diabetes.

Results and conclusions:
The investigators found that low carbohydrate diet significantly reduced HbA1c level [WMD = -0.44, 95% CI = -0.61 to -0.26, p= 0.00] of patients with type 2 diabetes.

The investigators found that low carbohydrate diet significantly reduced triglycerides concentration [WMD = -0.33, 95% CI = -0.45 to -0.21, p = 0.00] of patients with type 2 diabetes.

The investigators found that low carbohydrate diet significantly increased HDL cholesterol concentration (WMD = 0.07, 95% CI = 0.03 to 0.11, p = 0.00] of patients with type 2 diabetes.

The investigators found that low carbohydrate diet was not associated with decreased level of total cholesterol and LDL cholesterol.

The investigators found subgroup analyses showed that short term intervention of low carbohydrate diet was effective for weight loss [WMD = -1.18, 95% CI = -2.32 to -0.04, p = 0.04] in patients with type 2 diabetes.

The investigators concluded there is a beneficial effect of low carbohydrate diet intervention on glucose control in patients with type 2 diabetes. The low carbohydrate diet intervention also has a positive effect on triglycerides and HDL cholesterol concentrations, but without significant effect on long term weight loss.

Original title:
Efficacy of low carbohydrate diet for type 2 diabetes mellitus management: A systematic review and meta-analysis of randomized controlled trials by Meng Y, Bai H, […], Chen L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28750216

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

A low carbohydrate diet is a diet that is largely made up of meals/products with 20-40 En% carbohydrate. Practically, this means that all meals/products that you eat on a daily basis should on average contain 20-40 En% carbohydrate.
20-40 En% carbohydrate means that the total amounts of carbohydrate make up for a 20-40% of the total kcal of the diet. Check here which products contain 20-40 En% carbohydrate.

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:
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:
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

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

Objectives:
Iron deficiency is a prevalent nutritional disease and fatigue is a common complaint in the general and patient population, however, the association between iron deficiency without anaemia (IDNA) and fatigue is unclear. Therefore, this review article (meta-analysis) has been conducted.

Does improving iron status decrease fatigue in patients with iron deficiency without anaemia?

Study design:
This review article included a total of 6 RCTs and 6 cross-sectional studies.

Results and conclusions:
The investigators found in the meta-analysis of 6 RCTs, a significant therapeutic effect of iron supplements in fatigue patients with iron deficiency without anaemia [pooled effect size = 0.33, 95% CI = 0.17 to 0.48, I2 = 0.0%, p 0.0001]. A sensitivity analysis found that the overall results (i.e. significant association) were robust.

The investigators found in the meta-analysis of 6 cross-sectional studies, a non-significant therapeutic effect of iron supplements in fatigue patients with iron deficiency without anaemia [pooled effect size = 0.10, 95% CI = -0.11 to 0.31, I2 = 57.4%, p = 0.362]. A sensitivity analysis found that the overall results (i.e. no significant association) were not robust, however, removal of one study made the outcomes significant.

The investigators concluded improving iron status decreases fatigue in patients with iron deficiency without anaemia. However, further research is necessary to identify diagnostic criteria for selecting fatigue patients who might benefit from iron therapy and to assess the prevalence of patients with iron deficiency without anaemia in the general population.

Original title:
Iron deficiency without anaemia is a potential cause of fatigue: meta-analyses of randomised controlled trials and cross-sectional studies by Yokoi K and Konomi A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28625177

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

Objectives:
It has been unclear whether supplemental probiotics therapy improves clinical outcomes in type 2 diabetic patients. Therefore, this meta-analysis (systematic review) has been conducted.

Do probiotics supplements improve clinical outcomes in type 2 diabetic patients?

Study design:
This review article included 12 RCTs involving 684 type 2 diabetic patients.

Results and conclusions:
The investigators found a significant decreased glucose level in the probiotics group [pooled standardized mean difference = -0.18 mg/dL, 95% CI = -0.35 to -0.01, p = 0.04, I2 = 64%, p = 0.004] compared to the control group.

The investigators found a significant reduction in HbA1c in the probiotics group [pooled standardized mean difference = -0.38%, 95% CI = -0.62 to -0.14, p = 0.002, I2 = 0%, p = 0.72] compared to the control group.

The investigators found a significant reduction in fasting insulin level in the probiotics group [pooled standardized mean difference = -0.38, 95% CI = -0.59 to -0.18, p = 0.003, I2 = 0%, p = 0.81] compared to the control group.

The investigators found a significant reduced HOMA-IR level in the probiotics group [pooled standardized mean difference = -0.99, 95% CI = -1.52 to -0.4, p = 0.0002, I2 = 86%, p 0.00001] compared to the control group.

The investigators found a significant reduced CRP level in the probiotics group [pooled standardized mean difference = -1.34 mg/L, 95% CI = -1.76 to -0.92, p 0.00001, I2 = 90%, p 0.00001] compared to the control group.

The investigators found a non-significant reduction in both triglyceride levels [SMD = -0.23, 95% CI = -0.48 to 0.02, p = 0.07, I2 = 52%, p = 0.03] and cholesterol levels [total cholesterol: SMD = -0.18, 95% CI = -0.42 to 0.06, p = 0.14, I2 = 47%, p = 0.05 and LDL-cholesterol: SMD = -0.03, 95% CI = -0.20 to 0.14, p = 0.73, I2 = 3%, p = 0.41] in the probiotics group compared to the control group.

The investigators concluded that probiotics supplementation is associated with significant improvement in HbA1c and fasting insulin in type 2 diabetes patients. These results may provide evidence for encouraging use of probiotics in patients with type 2 diabetes mellitus. However, more randomized placebo-controlled trials with larger sample sizes are warranted to confirm these findings.

Original title:
Effect of Probiotics on Glucose and Lipid Metabolism in Type 2 Diabetes Mellitus: A Meta-Analysis of 12 Randomized Controlled Trials by Yao K, Zeng L, [...], Zou X.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5491138/

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

Objectives:
Dietary intake is potentially associated with the onset of Crohn’s disease (CD), but evidence from epidemiological studies has remained unclear. Therefore, this review article (meta-analysis) has been conducted.

Is there a positive association between fat, carbohydrate or protein intake and the risk of Crohn’s disease?

Study design:
This review article included 4 case-control studies with a total of 311 Crohn’s disease cases and 660 controls and 5 prospective cohort studies with a total of 238,887 participants and 482 Crohn’s disease cases.

The Egger’s test detected no obvious publication bias in fiber (p = 0.708), while there were not enough studies to conduct the analyses for carbohydrate, fat and protein.

Results and conclusions:
The investigators found no evidence of a non-linear relationship between total carbohydrate intake and Crohn’s disease risk [p for non-linearity = 0.376].

The investigators found no association between 10 g increment/day of total carbohydrate intake and Crohn’s disease risk [RR = 0.991, 95% CI = 0.978-1.004, I2 = 0.0%, p = 0.439]. No association because RR of 1 was found in the 95% CI of 0.978 to 1.004. RR of 1 means no risk/association.

The investigators found no evidence of a non-linear relationship between total fat intake and Crohn’s disease risk [p for non-linearity = 0.281].

The investigators found no association between 10 g increment/day of total fat intake and Crohn’s disease risk [RR = 1.018, 95% CI = 0.969-1.069, I2 = 44.6%, p = 0.125].

The investigators found no evidence of a non-linear relationship between total protein intake and Crohn’s disease risk [p for non-linearity = 0.163].

The investigators found no association between 10 g increment/day of total protein intake and Crohn’s disease risk [RR = 1.029, 95% CI = 0.955-1.109, I2 = 54.7%, p = 0.085].

The investigators found a non-linear relationship between fiber dietary intake and Crohn’s disease risk [p for non-linearity = 0.019].

The investigators found a significant reduced risk of 14.7% for Crohn’s disease for per 10 g increment/day of fiber [RR = 0.853, 95% CI = 0.762-0.955]. However, the protective role of fiber dietary intake in the development of Crohn’s disease was gone after adjustment for the risk factor smoking [RR for per 10 g increment/day = 0.890, 95% CI = 0.776-1.020].

The investigators found a non-linear relationship between sucrose intake and Crohn’s disease risk [p for non-linearity = 0.023].

The investigators found a significant increased risk of 8.8% for Crohn’s disease for per 10 g increment/day of sucrose [RR = 1.088, 95% CI = 1.020-1.160, I2 = 0.0%, p = 0.39]. Significant means it can be said with a 95% confidence that each 10 g increment/day of sucrose really increased the risk of Crohn’s disease. 

The investigators concluded there is a lack of association between total carbohydrate, fat or protein intake and the risk of Crohn’s disease, while high fiber dietary intake might decrease the risk but the association was influenced by study design and smoking adjustment. High sucrose intake might increase the risk of Crohn’s disease. However, large-scale prospective designed studies are needed to confirm these findings.

Original title:
Macronutrient Intake and Risk of Crohn’s Disease: Systematic Review and Dose–Response Meta-Analysis of Epidemiological Studies by Zeng L, Hu S, [...], Tan Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452230/

Additional information of El Mondo:
Find more information/studies on fat, protein, carbohydrate and fiber right here.

 

Objectives:
C-reactive protein (CRP) has been proposed as a risk marker and risk factor of cardiovascular disease. There have been a number of clinical reports suggesting that supplementation with L-carnitine can modulate systemic inflammation and lower circulating CRP concentrations, but the results have not been consistent. Therefore, this review article (meta-analysis) has been conducted.

Does supplementation with L-carnitine reduce circulating CRP concentrations?

Study design:
This review article included 6 RCTs comprising 541 cases and 546 controls.
3 studies were conducted in diabetic or prediabetic patients, 2 studies in hemodialysis patients and 1 study in patients with non-alcoholic steatohepatitis.
Duration of L-carnitine supplementation ranged between 8 to 48 weeks.
Dosage of L-carnitine ranged between 1-2 g/day in all the included trials.

Results and conclusions:
The investigators found in random effect analysis a statistically significant pooled effect size [net change = -0.39 mg/L, 95% CI = -0.62 to -0.16, p = 0.001, I2 = 44%, p = 0.11] for the impact of L-carnitine supplementation among 541 cases and 546 controls. This effect size estimate was found to be robust and remained unaffected by the removal of each single study.

The investigators concluded the present meta-analysis support the clinically relevant benefit of L-carnitine supplementation (1-2 g/day) in lowering the circulating levels of CRP. Conducting future, large-scale, randomized clinical trials is warranted in homogenous populations to verify the findings of this meta-analysis.

Original title:
Effect of L-carnitine Supplementation on Circulating C-reactive Protein Levels: A Systematic Review and Meta-Analysis by Sahebkar A.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4922328/

Additional information of El Mondo:
Find more information/studies on L-carnitine and chronic diseases right here.

Higher circulating levels of CRP increase inflammation.
 

Objectives:
Is there a causal association between low serum vitamin D concentrations, increased body mass index (BMI) and pediatric-onset multiple sclerosis (MS) using genetic risk scores (GRS)?

Study design:
This review article included participants of non-Hispanic white individuals recruited from over 15 sites across the United States (n = 394 cases, 10,875 controls) and Sweden (n = 175 cases, 5,376 controls; total n = 16,820).

Results and conclusions:
The investigators found meta-analysis findings demonstrated that a vitamin D GRS associated with increasing levels of 25(OH)D in serum significantly decreased risk of pediatric-onset MS with 28% [OR =  0.72, 95% CI = 0.55-0.94, p = 0.02] after controlling for sex, genetic ancestry, HLA-DRB1*15:01 and over 100 non-human leukocyte antigen MS risk variants.

The investigators also found that a higher BMI GRS significant increased risk of pediatric-onset MS with 17% [OR = 1.17, 95% CI = 1.05-1.30, p = 0.01] after adjusting for covariates.

The investigators found estimates for each GRS were unchanged when considered together in a multivariable model.

The investigators concluded evidence supporting independent and causal effects of decreased vitamin D levels and increased BMI on susceptibility to pediatric-onset MS.

Original title:
Evidence for a causal relationship between low vitamin D, high BMI, and pediatric-onset MS by Gianfrancesco MA, Stridh P, […], Waubant E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28356466

Additional information of El Mondo:
Find more information/studies on chronich disease and vitamin D right here.
 

Objectives:
What is the relationship between intake of 12 major food groups and risk of type 2 diabetes (T2D)?

Study design:
This review article included prospective cohort studies.
The 12 major food groups are whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat and sugar-sweetened beverages (SSB).

The meta-evidence was graded "low" for legumes and nuts; "moderate" for refined grains, vegetables, fruit, eggs, dairy and fish; and "high" for processed meat, red meat, whole grains and sugar-sweetened beverages.

Results and conclusions:
The investigators found 6 out of the 12 food-groups showed a significant relation with risk of type 2 diabetes; 3 of them a decrease of risk with increasing consumption (whole grains, fruits and dairy) and 3 an increase of risk with increasing consumption (red meat, processed meat and sugar-sweetened beverages) in the linear dose-response meta-analysis.

The investigators found evidence of a non-linear relationship between fruits, vegetables, processed meat, whole grains and sugar-sweetened beverages and type 2 diabetes risk.

The investigators found optimal consumption of risk-decreasing foods resulted in a 42% reduction and consumption of risk-increasing foods was associated with a threefold type 2 diabetes risk, compared to non-consumption.

The meta-evidence was graded "low" for legumes and nuts; "moderate" for refined grains, vegetables, fruit, eggs, dairy and fish; and "high" for processed meat, red meat, whole grains, and sugar-sweetened beverages. Among the investigated food groups, selecting specific optimal intakes can lead to a considerable change in risk of type 2 diabetes.

The investigators concluded that a higher consumption of whole grains, fruits and dairy products reduces type 2 diabetes risk, while a higher consumption of red meat, processed meat and sugar-sweetened beverages increases type 2 diabetes risk.

Original title:
Food groups and risk of type 2 diabetes mellitus: a systematic review and meta-analysis of prospective studies by Schwingshackl L, Hoffmann G, […], Boeing H.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28397016

Additional information of El Mondo:
Find more information/studies on consumption of meat, fruit, dairy products and nuts and type 2 diabetes right here.

Objectives:
Olive oil (OO) as food is composed mainly of fatty acids and bioactive compounds depending from the extraction method. Both had been discussed as health promoting with still open questions. Therefore, this meta-analysis (systematic review) has been conducted.

Does olive oil intake reduce risk of type 2 diabetes?

Study design:
This review article included 4 cohort studies including 15,784 type 2 diabetes cases and 29 intervention trials.

Results and conclusions:
The investigators found the highest olive oil intake category showed a 16% reduced risk of type 2 diabetes [RR = 0.84, 95% CI = 0.77, 0.92) compared with the lowest. The reduced risk was significant.

The investigators found evidence for a nonlinear relationship between olive oil intake and the reduced risk of type 2 diabetes.

The investigators found in patients with type 2 diabetes that olive oil supplementation resulted in a significantly more pronounced reduction in HbA1c [MD = -0.27%, 95% CI = -0.37 to -0.17] and fasting plasma glucose [MD = -0.44 mmol/L, 95% CI = -0.66 to -0.22] as compared with the control groups.

The investigators concluded that the intake of olive oil is beneficial for the prevention and management of type 2 diabetes. This conclusion regards olive oil as food and might not been valid for single components comprising this food.

Original title:
Olive oil in the prevention and management of type 2 diabetes mellitus: a systematic review and meta-analysis of cohort studies and intervention trials by Schwingshackl L, Lampousi AM, […], Boeing H1.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28394365

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

Objectives:
Nutrition therapy is an integral part of self-management education in patients with type 2 diabetes. Carbohydrates with a low glycemic index are recommended, but the ideal amount of carbohydrate in the diet is unclear. Therefore, this meta-analysis (systematic review) has been conducted.

Has carbohydrate restriction (below 45 En% carbohydrate) beneficial effects on glycemic control in type 2 diabetes?

Study design:
This review article included 10 RCTs. In total, 1,376 subjects with type 2 diabetes were included in this analysis. Forty-nine percent were male and the average age was 58 years. The majority were obese; mean BMI ranged from 26 kg/m² in an Asian population to 37 kg/m² in an American population.

The duration of the intervention varied from 3 to 24 months.

The average predefined targets for the assigned carbohydrate restriction were 25 En% (range 14-40 En%). The average reported intake was 30 En% (range 14-45 En%) after 3 or 6 months of intervention and 38 En% (range 27-45 En%) at 1 year (5 trials).

Results and conclusions:
The investigators found following a carbohydrate diet of 30 En% (range 14-45 En%) during 3 to 6 months significantly reduced HbA1c level of patients with type 2 diabetes with 0.34% [95% CI = 0.06 to 0.63] compared with a diet of 45-60 En% carbohydrate (high-carbohydrate diet).
Owing to heterogeneity, however, the quality of the evidence for this is only moderate. However, at 1 year or later, HbA1c level (seven trials included) was similar in the two groups.

The investigators found the greater the carbohydrate restriction, the greater the glucose-lowering effect [R = -0.85, p 0.01].

The investigators found the effect of the 2 types of diet on BMI/body weight, LDL cholesterol, QoL and attrition rate was similar throughout interventions.

The investigators concluded that carbohydrate restriction (below 45 En% carbohydrate) has a greater effect on glycemic control in type 2 diabetes than an high-carbohydrate diet in the short term. The magnitude of the effect was correlated to the carbohydrate intake, the greater the restriction, the greater glucose lowering, a relationship that has not been demonstrated earlier. However, in the long term, the glucose-lowering effect of high-carbohydrate diet (HCD) and low-carbohydrate diets (LCD) was similar.

Original title:
Systematic review and meta-analysis of dietary carbohydrate restriction in patients with type 2 diabetes by Snorgaard O, Poulsen GM, [...], Astrup A.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5337734/

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

Objectives:
Recent studies have found that the serum zinc levels were associated with the risk of Parkinson's disease (PD), but the results were inconsistent. Therefore, this meta-analysis (review article) has been conducted.

Is there an association between serum zinc levels and Parkinson's disease risk?

Study design:
This review article included 11 articles involving 822 Parkinson's disease patients and 777 healthy controls (subjects without Parkinson's disease).

No publication bias was found.

Results and conclusions:
The investigators found that the serum zinc levels in Parkinson's disease patients were significantly lower than those in health controls [SMD = -0.779, 95% CI = -1.323 to -0.234, p 0.001].

This association was also significant in oriental studies [SMD = -1.601, 95% CI = -2.398 to -0.805, p 0.001].

The investigators concluded that serum zinc levels in Parkinson's disease patients are significantly lower than those in healthy controls.

Original title:
Association Between Serum Zinc Levels and the Risk of Parkinson's Disease: a Meta-Analysis by Sun H, Liu X, […], Li W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28160244

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

Objectives:
Randomised controlled trials (RCTs) have observed contrasting results on the effects of vitamin C on circulating biomarkers of glycaemic and insulin regulation. Therefore, this meta-analysis (systematic review) has been conducted.

Has vitamin C supplementation a favorable effect on circulating biomarkers of glycaemic and insulin regulation?

Study design:
This review article included 22 RCTs with 937 participants.

Results and conclusions:
The investigators found overall, vitamin C supplementation did not modify glucose, HbA1c and insulin concentrations.

The investigators found, however, subgroup analyses showed that vitamin C supplementation significantly reduced glucose concentrations with 0.44 mmol/L [95% CI = -0.81 to -0.07, p =0.01] in patients with type 2 diabetes and in interventions with a duration greater than 30 days [-0.53%, 95% CI = -0.79 to -0.10, p = 0.02].

The investigators found vitamin C administration had greater effects on fasting [-13.63 pmol/L, 95% CI = -22.73 to -4.54, p 0.01] compared to postprandial insulin concentration. However, meta-regression analyses showed that age was a modifier of the effect of vitamin C on insulin concentration.

The investigators found the effect size of vitamin C supplementation was associated with baseline BMI and plasma glucose levels and with the duration of the intervention.

The investigators concluded vitamin C supplementation has greater reduction in glucose concentrations in patients with type 2 diabetes, older individuals and with more prolonged supplementation (greater than 30 days). Personalized interventions with vitamin C may represent a feasible future strategy to enhance benefits and efficacy of interventions. Nevertheless, results need to be interpreted cautiously due to limitations in the primary studies.

Original title:
Effects of vitamin C supplementation on glycaemic control: a systematic review and meta-analysis of randomised controlled trials by Ashor AW, Werner AD, […], Siervo M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28294172

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

Objectives:
Does magnesium supplementation reduce risk of cardiovascular disease among diabetic subjects?

Study design:
This review article included RCTs.

Results and conclusions:
The investigators found magnesium supplementation significantly improved fasting plasma glucose with 4.641 mg/dL [WMD = -4.641 mg/dL, 95% CI = -7.602 to -1.680, p = 0.002]. A more beneficial effect of magnesium supplementation was observed in diabetic subjects with hypomagnesaemia.

The investigators found magnesium supplementation significantly improved high-density lipoprotein (HDL or good cholesterol) with 3.197 mg/dL [WMD = 3.197 mg/dL, 95% CI = 1.455 to 4.938, p 0.001]. A more beneficial effect of magnesium supplementation was observed in diabetic subjects with hypomagnesaemia.

The investigators found magnesium supplementation significantly improved low-density lipoprotein (LDL or bad cholesterol) with 10.668 mg/dL [WMD = -10.668 mg/dL, 95% CI = -19.108 to -2.228, p = 0.013]. A more beneficial effect of magnesium supplementation was observed in diabetic subjects with hypomagnesaemia.

The investigators found magnesium supplementation significantly improved plasma triglycerides with 15.323 mg/dL [WMD = -15.323 mg/dL, 95% CI = -28.821 to -1.826, p = 0.026]. A more beneficial effect of magnesium supplementation was observed in diabetic subjects with hypomagnesaemia.

The investigators found magnesium supplementation significantly improved systolic blood pressure with 3.056 mmHg [WMD = 3.056 mmHg, 95% CI = -5.509 to -0.603, p = 0.015]. A more beneficial effect of magnesium supplementation was observed in diabetic subjects with hypomagnesaemia.

The investigators concluded magnesium supplementation has a favourable effect on risk factors of cardiovascular diseases. Although future large RCTs are needed for making robust guidelines for clinical practice.

Original title:
Effect of magnesium supplementation on type 2 diabetes associated cardiovascular risk factors: a systematic review and meta-analysis by Verma H and Garg R.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28150351

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

Objectives:
The conclusions from epidemiological studies are controversial between apple and pear consumption and type 2 diabetes mellitus (T2DM) risk. Therefore, this meta-analysis (systematic review) has been conducted.

Study design:
This review article included a total of 5 independent prospective cohort studies with 14,120 T2DM incident cases among 228,315 participants.

Results and conclusions:
The investigators found consumption of apples and pears was associated with 18% reduction in type 2 diabetes mellitus risk [multivariate-adjusted relative risk = 0.82, 95% CI = 0.75-0.88, I2 = 0.00%] when comparing the highest versus lowest category.

The investigators found dose-response analysis showed that one serving per week increment of apple and pear consumption was associated with a 3% [95% CI = 0.96-0.98, p for trend 0.001] reduction in type 2 diabetes mellitus risk.

The investigators concluded a higher consumption of apples and pears; at least one serving per week reduces type 2 diabetes mellitus risk.

Original title:
Apple and pear consumption and type 2 diabetes mellitus risk: a meta-analysis of prospective cohort studies by Guo XF, Yang B, […], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28186516

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

The standard serving size is a 1/2 cup of sliced fruit. A medium pear produces approximately 1 cup of fruit; so an average medium pear equals two fruit servings.
1 small apple = 1 serving.
 

Objectives:
Is there an association between folate level and the risk of schizophrenia?

Study design:
This review article included 16 high quality studies with a total of 1,183 (52.1%) cases and 1,089 (47.9%) controls.

There was no publication bias based on Egger’s and Begg’s tests [p = 0.48 and 0.30, respectively].

Results and conclusions:
The investigators found folate level in schizophrenia patients was significantly lower than that in healthy controls [SMD = -0.65, 95% CI = -0.86 to -0.45, p 0.00001].

The investigators found in subgroup analysis a decreased folate level in both Asian and European patients (SMD = -0.86, p 0.00001 and SMD = -0.44, p 0.00001, respectively], while there were no significant differences in patients from other areas [p > 0.05].

The investigators found sensitivity analysis confirmed that these results were stable and reliable.

The investigators concluded decreased folate level is a risk factor for schizophrenia, especially in Asian and European patients. More epidemiological and biochemistry studies are required to describe how folate or folate supplementation play roles in the progress of schizophrenia.

Original title:
Folate Deficiency Increased the Risk of Schizophrenia: a Meta-Analysis by Ding Y, Ju M, […], He L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28124599

Additional information of El Mondo:
Find more information/studies on folate right here.
The folate level of the human body can be increased by dietary folate intake and/or taking folate supplements.