Nutritional advice

Objectives:
Are growth parameters at birth associated with maternal urinary iodine concentration (UIC) or normal ranges of thyroid hormones during pregnancy?

Study design:
This review article included 11 studies.

The pooled mean birth weight, length and head circumference values and 95% confidence intervals were estimated in newborns born to women with UIC  150 μg/L and UIC ≥150 μg/L during pregnancy.

Results and conclusions:
The investigators found pooled mean birth weight, length and head circumference in newborns whose mothers had UIC  150 μg/L vs UIC ≥150 μg/L were 2,898g vs 2,900g [p = 0.970], 49.6 cm vs 49.4 cm [p = 0.880] and 34.0 cm vs 34.1 cm [p = 0.933], respectively.

The investigators found dose-response meta-analyses revealed no significant linear or nonlinear associations between maternal urinary iodine concentration during pregnancy and anthropometric measures at birth.

The investigators found high vs normal values of maternal free thyroxine and thyrotropin during pregnancy were inversely associated with neonatal birth weight.

The investigators concluded that birth weight is affected by even mild variations in the normal concentrations of maternal thyroid hormones. However, in the current meta-analysis, birth anthropometric measures are not associated with maternal urinary iodine concentration during pregnancy.

Original title:
Do maternal urinary iodine concentration or thyroid hormones within the normal range during pregnancy affect growth parameters at birth? A systematic review and meta-analysis by Nazeri P, Shab-Bidar S, […], Shariat M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31923312

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

Objectives:
Lead is a known risk factor for amyotrophic lateral sclerosis (ALS). However, the results of studies exploring the relationship between lead exposure and the occurrence of ALS are inconsistent. Therefore, this review article has been conducted.

Does a high lead exposure increase risk of ALS?

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

Results and conclusions:
The investigators found a high lead exposure significantly increased risk of ALS with 28% [OR = 1.28, 95% CI = 1.02 to 1.63].
Subgroup and sensitivity analyses showed stable results.

The investigators concluded a high lead exposure increases risk of ALS.

Original title:
Population-based study of environmental/occupational lead exposure and amyotrophic lateral sclerosis: a systematic review and meta-analysis by Meng E, Mao Y, […], Jin W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31578652

Additional information of El Mondo:
Find here more information/studies about chronic diseases.
 

Objectives:
Low-carbohydrate diets are associated with cardiovascular risk factors; however, the results of different studies are inconsistent. Therefore, this review article has been conducted.

Do low-carbohydrate diets (diets with less than 40 En% carbohydrates) reduce cardiovascular risk factors?

Study design:
This review article included 12 RCTs with a total of 820 in the observation group (intervention group or low carbohydrate group) and 820 in the control group. The largest sample size was 403 cases and the smallest was 42 cases. The patients’ ages ranged from 31 to 65 years old.
The intervention was a diet with less than 40 En% carbohydrates in the observation group and a diet with 45 En% to 55 En% carbohydrates in the control group.

Results and conclusions:
The investigators found compared with the control group, the triglyceride levels of the low-carbohydrate group (less than 40 En% carbohydrates) significantly decreased by 0.15 mmol/L [95% CI = -0.23 to -0.07, I2 = 75%, p = 0.001].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The results of the publication bias analysis showed that the funnel plot was not symmetric. The asymmetry of the funnel plot may have been caused by publication bias and other issues.

The investigators found in subgroup analyses, low-carbohydrate diet interventions lasting less than 6 months significantly decreased the triglyceride levels by 0.23 mmol/L [95% CI = -0.32 to -0.15] and those of 12-23 months decreased the levels by 0.17 mmol/L [95% CI = -0.32 to -0.01].

The investigators found compared with the control group, the plasma HDL-cholesterol level (good cholesterol) of the low-carbohydrate group significantly increased by 0.1 mmol/L [95% CI = 0.08 to 0.12, I2 = 41%, p = 0.02].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The investigators found in subgroup analyses, the increase in plasma HDL-cholesterol levels was 0.08 mmol/L [95% CI = 0.27 to 0.57] for interventions lasting less than 6 months, 0.12 mmol/L [95% CI = 0.09 to 0.15] for those lasting 6-11 months, 0.12 mmol/L [95% CI = 0.08 to 0.15] for those lasting 12-23 months and 0.08 mmol/L [95% CI = 0.04 to 0.12] for those lasting 24 months. 

The investigators found compared with the control group, the serum total cholesterol level of the low-carbohydrate group significantly increased by 0.13 mmol/L [95% CI = 0.08 to 0.19].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The investigators found compared with the control group, the plasma LDL-cholesterol level (bad cholesterol) of the low-carbohydrate group significantly increased by 0.11 mmol/L [95% CI = 0.02 to 0.19, I2 = 71%, p = 0.0001].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The investigators found compared with the control group, the body weight of the low-carbohydrate group significantly decreased by 1.58 kg [95% CI = -1.58 to -0.75, I2 = 49%, p = 0.01].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The investigators found in subgroup analyses, the decrease in body weight was 1.14 kg [95% CI = -1.65 to -0.63] for interventions lasting less than 6 months and 1.73 kg [95% CI = -2.7 to -0.76] for those lasting 6-11 months.

The investigators found compared with the control group, the overall systolic blood pressure of the low-carbohydrate group significantly decreased by 1.41 mmHg [95% CI = -2.26 to -0.56, I2 = 0%, p = 0.84].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The investigators found in subgroup analyses, the overall systolic blood pressure significantly decreased by 2.97 mmHg [95% CI = -4.62 to -1.31] in the group that received interventions lasting less than 6 months.

The investigators found compared with the control group, the diastolic blood pressure of the low-carbohydrate group significantly decreased by 1.71 mmHg [95% CI = -2.36 to -1.06, I2 = 14%, p = 0.29].
The results remained unchanged in the sensitivity analysis (after subtracting each of the included studies individually).

The investigators found in subgroup analyses, the diastolic blood pressure significantly decreased by 2.76 mmHg [95% CI = -4.07 to -1.46] in the group that received interventions lasting less than 6 months and 2.11 mmHg [95% CI = -3.28 to -0.93] for those lasting 6-11 months.

The investigators concluded low-carbohydrate diets (diets less than 40 En% carbohydrates) have beneficial effects on cardiovascular risk factors at less than 6 months and 6-11 months, but after 2 years of a low-carbohydrate diet, there is no significant effect on cardiovascular risk factors.

Original title:
The effects of low-carbohydrate diets on cardiovascular risk factors: A meta-analysis by Dong T, Guo M, [...], Chen B.

Link:
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0225348

Additional information of El Mondo:
Find more information/studies on carbohydrate consumption and cardiovascular diseases right here.

40 En% carbohydrates means that the total amounts of carbohydrate make up for a 40% of the total kcal of the diet. The easiest way to follow this diet is to choose only meals/products that also contain 40 En% carbohydrates. These products in the supermarket contain 40 En% carbohydrates.

Objectives:
Previous findings on the associations of legume and soy intake with the risk of type 2 diabetes are conflicting. Therefore, this review article (meta-analysis) has been conducted.

Does legume or soy dietary intake reduce risk of type 2 diabetes?

Study design:
This review article included 15 unique cohort studies with a total of 565,810 individuals and 32,093 incident cases (persons with type 2 diabetes).

Overall quality of evidence was rated as moderate for total legumes and low for total soy and soy subtypes.

Results and conclusions:
The investigators found no association between total legumes dietary intake and risk of type 2 diabetes [summary RR = 0.95, 95% CI = 0.79 to 1.14, I2 = 84.8%].
No association because RR of 1 was found in the 95% CI of 0.79 to 1.14. RR of 1 means no risk/association.

The investigators found no association between total soy dietary intake and risk of type 2 diabetes [summary RR = 0.83, 95% CI = 0.68 to 1.01, I2 = 90.8%].

The investigators found no association between soy milk dietary intake and risk of type 2 diabetes [summary RR = 0.89, 95% CI = 0.71 to 1.11, I2 = 91.7%].

The investigators found tofu dietary intake significantly reduced risk of type 2 diabetes with 8% [summary RR = 0.92, 95% CI = 0.84 to 0.99].
Significantly because RR of 1 was not found in the 95% CI of 0.84 to 0.99. RR of 1 means no risk/association.

The investigators found soy protein dietary intake significantly reduced risk of type 2 diabetes with 16% [summary RR = 0.84, 95% CI = 0.75 to 0.95].

The investigators found soy isoflavones dietary intake significantly reduced risk of type 2 diabetes with 12% [summary RR = 0.88, 95% CI = 0.81 to 0.96].

The investigators found in dose-response analysis, significant linear inverse associations for tofu, soy protein and soy isoflavones [all p 0.05].

The investigators concluded dietary intakes of tofu, soy protein and soy isoflavones reduce incident type 2 diabetes. These findings support recommendations to increase intakes of certain soy products for the prevention of type 2 diabetes. However, the overall quality of evidence was low and more high-quality evidence from prospective studies is needed.

Original title:
Legume and soy intake and risk of type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies by Tang J, Wan Y, […], Feng F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31915830

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

Objectives:
Which factors increase risk of dementia?

Study design:
This review article included 34 prospective cohort studies, among which 24 were eligible for meta-analysis. A total of 159,594 non-demented adults were enrolled at baseline before 65 years and 13,540 people were diagnosed with dementia after follow-up.

Results and conclusions:
The investigators found obesity significantly increased risk of dementia with 78% [RR = 1.78, 95% CI = 1.31-2.41].

The investigators found diabetes mellitus significantly increased risk of dementia with 69% [RR = 1.69, 95% CI = 1.38-2.07].

The investigators found current smoking significantly increased risk of dementia with 61% [RR = 1.61, 95% CI = 1.32-1.95].

The investigators found hypercholesterolemia significantly increased risk of dementia with 57% [RR = 1.57, 95% CI = 1.19-2.07].
However, the sensitivity analyses showed that the result of hypercholesterolemia was not reliable, which need to be confirmed by more high-quality studies.

The investigators found hypertension significantly increased risk of dementia with 41% [RR = 1.41, 95% CI = 1.23-1.62] for borderline blood pressure.

The investigators found hypertension significantly increased risk of dementia with 72% [RR = 1.72, 95% CI = 1.25-2.37] for high systolic blood pressure.
However, the sensitivity analyses showed that the result of high systolic blood pressure was not reliable, which need to be confirmed by more high-quality studies.

The investigators found hyperhomocysteinemia, psychological stress and heavy drinking were also associated with elevated dementia risk.

The investigators found, in addition, physical exercise, a healthy diet and hormone therapy in middle age were associated with the reduction of dementia risk.

The investigators concluded middle-aged people with obesity or diabetes and current smokers in midlife are at higher risk of developing dementia later in life.

Original title:
Midlife Modifiable Risk Factors for Dementia: A Systematic Review and Meta-analysis of 34 Prospective Cohort Studies by Li XY, Zhang M, [...], Tan L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31902364

Additional information of El Mondo:
Find more information/studies on obesity, diabetes, hypertension and dementia right here.
 

Objectives:
Many studies have been reported that dietary meat intake may be associated with the risk of asthma in children, but the results are inconsistent. Therefore, this review article has been conducted.

Does dietary meat intake increase asthma in children?

Study design:
This review article included a total of 9 articles.

No publication bias was detected.

Results and conclusions:
The investigators found dietary meat intake 3 or more times per week compared with never/occasionally intake had no significant association with asthma risk among children [OR = 1.27, 95% CI  =  0.80-2.01, p =  0.308].
Not significant because OR of 1 was found in the 95% CI of 0.80 to 2.01. OR of 1 means no risk/association.

The investigators found, similarly, daily dietary intake of meat did not affect the risk of asthma in children when compared with never/occasionally intake [OR  =  1.13, 95% CI  =  0.93-1.37, p  =  0.234].

The investigators concluded dietary meat intake is not a risk factor for asthma in children. Due to some limitations that exist in this review article, more studies are needed to further assess the association between dietary meat intake and asthma risk in children.

Original title:
Dietary meat intake and risk of asthma in children: evidence from a meta-analysis by Zhang D, Cao L, [...], Wang Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31895767

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Find here more information/studies about meat consumption and chronic diseases.
 

Objectives:
Does dietary intake of garlic reduce risk of colorectal cancer?

Study design:
This review article included 11 studies involving 12,558 cases (persons with colorectal cancer).

There was no notable evidence of publication bias.

Results and conclusions:
The investigators found for the highest versus the lowest garlic consumption categories, a significantly reduced risk of 20% [integrated relative risk = 0.80, 95% CI = 0.69 to 0.91] for colorectal cancer.
The sensitivity analysis revealed no notable alterations of the integrated results.
Significant means that there is an association with a 95% confidence.

The investigators found in case-control studies for the highest versus the lowest garlic consumption categories, a significantly reduced risk of 29% [relative risk = 0.71, 95% CI = 0.60 to 0.84] for colorectal cancer.
Significant because relative risk of 1 was not found in the 95% CI of 0.60 to 0.84. Relative risk of 1 means no risk/association.

The investigators found in cohort studies for the highest versus the lowest garlic consumption categories, a non-significantly reduced risk of 1% [relative risk = 0.99, 95% CI = 0.80 to 1.23] for colorectal cancer.
Non-significantly because relative risk of 1 was found in the 95% CI of 0.80 to 1.23. Relative risk of 1 means no risk/association.

The investigators concluded that dietary intake of garlic could reduce risk of colorectal cancer. Could reduce because the risk was not significant in cohort studies.

Original title:
Garlic intake and the risk of colorectal cancer: A meta-analysis by Zhou X, Qian H, […], Zeng L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31895803

Additional information of El Mondo:
Find more information/studies on significantly/cohort studies, garlic consumption and colorectal cancer right here.

Objectives:
What is the effect of aerobic exercise performed in the fasted versus fed states on fat and carbohydrate metabolism in adults?

Study design:
This review article included 27 studies with a total of 273 participants.

Results and conclusions:
The investigators found a significant increase in fat oxidation during aerobic exercise (duration ≤120 min) performed in the fasted state compared with fed state [WMD = -3.08 g, 95% CI = -5.38 to -0.79, I2 = 39.1%].

The investigators found the weighted mean difference of onesterified fatty acids (NEFA) concentrations was not significantly different between states [WMD = 0.00 mmol/L, 95 % CI = -0.07 to 0.08, I2 = 72.7 %].

The investigators found, however, the weighted mean differences of glucose [WMD = 0.78 mmol/L, 95% CI = 0.43 to 1.14, I2 = 90.8%] and insulin concentrations [WMD = 104.5 pmol/L, 95% CI = 70.8 to 138.2, I2 = 94.5%] were significantly higher for aerobic exercise (duration ≤120 min) performed in the fed state.

The investigators concluded that aerobic exercise (duration ≤120 min) performed in the fasted state induces higher fat oxidation than aerobic exercise performed in the fed state.

Original title:
Effects of aerobic exercise performed in fasted v. fed state on fat and carbohydrate metabolism in adults: a systematic review and meta-analysis by Vieira AF, Costa RR, […], Kruel LF.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27609363

Additional information of El Mondo:
Find more studies/information on physical activity and energy right here.

Aerobic exercise is any exercise that raises the heart rate and increases respiration (breathing). Examples of aerobic exercise are:

• Cross-country skiing
• Cycling
• Dancing
• Fast walking
• Hiking
• Jogging or running
• Swimming
   

Objectives:
The association between elevated serum phosphorus concentration and cardiovascular or all-cause mortality yielded conflicting results. Therefore, this review article (meta-analysis) has been conducted.

Does an elevated serum phosphorus concentration increase cardiovascular and all-cause mortality in the general population?

Study design:
This review article included 6 prospective cohort studies involving 120,269 subjects.

Results and conclusions:
The investigators found when compared the highest with the reference concentration of serum phosphorus, a significant increased risk of 36% for cardiovascular mortality [pooled RR = 1.36, 95% CI = 1.07-1.72]. Significant because RR of 1 was not found in the 95% CI of 1.07 to 1.72. RR of 1 means no risk/association.

The investigators found when compared the highest with the reference concentration of serum phosphorus, a significant increased risk of 33% for all-cause mortality [pooled RR = 1.33, 95% CI = 1.15-1.58]. Significant means that there is an association with a 95% confidence.

The investigators found stratified analyses revealed that elevated serum phosphorus significantly increased all-cause mortality risk with 33% among men [RR 1.33, 95% CI = 1.11-1.60], but not in women [RR = 1.09, 95% CI = 0.89-1.33].

The investigators concluded elevated serum phosphorus concentration is independently associated with excessive risk of cardiovascular and all-cause mortality in the general population without chronic kidney disease. Serum phosphorus on all-cause mortality risk appears to be pronounced in men but exhibits no clear effect on women. However, gender difference of elevated serum phosphorus on mortality risk should be verified by more prospective cohort studies.

Original title:
Serum phosphorus, cardiovascular and all-cause mortality in the general population: A meta-analysis by Bai W, Li J and Liu J.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27475981

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

Objectives:
Reported associations between protein intake from different sources and type 2 diabetes (T2D) have been inconsistent.Therefore, this review article has been conducted.

Study design:
This review article included 11 prospective cohort studies with 505,624 participants and 37,918 type 2 diabetes cases (follow-up range: 5-24 years).

Results and conclusions:
The investigators found for the comparison of the highest with lowest categories of total protein intakes a significant higher risk of 9% for type 2 diabetes [RR = 1.09, 95% CI = 1.06 to 1.13]. Significant means that there is an association with a 95% confidence.

The investigators found for the comparison of the highest with lowest categories of animal protein intakes a significant higher risk of 19% for type 2 diabetes [RR = 1.19, 95% CI = 1.11 to 1.28].

The investigators found for the comparison of the highest with lowest categories of plant protein intakes a non-significant reduced risk of 5% for type 2 diabetes [RR = 0.95, 95% CI = 0.89 to 1.02]. Non-significant means it cannot be said with a 95% confidence that a daily higher intake of plant protein really reduced risk of type 2 diabetes with 5%.

The investigators found for the comparison of the highest with lowest categories of plant protein intakes a significant reduced risk of 7% for type 2 diabetes among women [RR = 0.93, 95% CI = 0.85 to 1.00].

The investigators found for the comparison of the highest with lowest categories of plant protein intakes a significant reduced risk of 9% for type 2 diabetes among US populations [RR = 0.91, 95% CI = 0.84 to 0.97].

The investigators concluded that a higher intake of total and animal protein are both associated with an increased risk of of type 2 diabetes. However, a higher intake of plant protein decreases risk of type 2 diabetes among women and US populations.

Original title:
Dietary protein intake and risk of type 2 diabetes: results from the Melbourne Collaborative Cohort Study and a meta-analysis of prospective studies by Shang X, Scott D, […], Sanders KM.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27629053

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

Objectives:
Micronutrient deficiencies impose a considerable burden of disease on many middle and low income countries. Several strategies have been shown to be effective in improving micronutrient deficiencies. However, the impact of fortified condiments as well as fortified noodles is less well documented. Therefore, this meta-analysis (review article) has been conducted.

What is the impact of micronutrient fortified condiments on hemoglobin, anemia and functional outcomes in children and adults (age: 5 to 50 years)?

Study design:
This review article included 14 RCTs comprising 8845 people with a mean age between 7.3 and 34 years. Mean follow-up was 0.88 years (range: 2.4 months to 2 years).

Only in 2 trials was multi-micronutrient fortification used, e.g. additional fortification with vitamin A, zinc and folate. In the other 12 studies, iron was the net difference in multi-micronutrient exposition between intervention and control groups.

Results and conclusions:
The investigators found in 12 RCTs that micronutrient fortification of condiments significantly increased hemoglobin concentrations by 0.74 g/dL [95% CI = 0.56 to 0.93].

The investigators found different types of iron preparations showed no differences in rise of hemoglobin concentrations (NaFeEDTA: 0.69 g/dL vs. 0.68 g/dL for other preparations).

The investigators found micronutrient fortification also led to a reduced risk of 41% for having anemia [risk ratio 0.59, 95% CI = 0.44 to 0.80].

The investigators found ferritin concentrations significantly increased with fortified condiments.

The investigators concluded the use of micronutrient fortified condiments can be a strategy to reduce anemia in children and adults due to micronutrient deficiencies beyond supplementation programs and fortification of staple food.

Original title:
Micronutrient Fortified Condiments and Noodles to Reduce Anemia in Children and Adults—A Literature Review and Meta-Analysis by Hess S, Tecklenburg L and Eichler K.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4772051/

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

Objectives:
Does garlic supplementation reduce cardiovascular disease risk?

Study design:
This review article included original studies and previous review articles (meta-analyses).

Results and conclusions:
The investigators found in 4 meta-analyses and 2 original studies that garlic supplementation significantly reduced blood pressure by 7-16 mmHg (systolic) and 5-9 mmHg (diastolic). Significant means that there is an association with a 95% confidence.

The investigators found in 8 meta-analyses that garlic supplementation significantly reduced total cholesterol by 7.4-29.8 mg/dL.

The most consistent benefits were shown in studies that used aged garlic extract (AGE).

The investigators found a few small studies that used aged garlic extract also showed favourable effects on C-reactive protein (CRP), pulse wave velocity (PWV), and coronary artery calcium (CAC).

Although garlic is generally safe, rare adverse reactions have been documented with limited causality established.

The investigators concluded garlic supplementation has the potential for cardiovascular protection based on risk factor reduction (hypertension and total cholesterol) and surrogate markers (C-reactive protein, pulse wave velocity and coronary artery calcium) of atherosclerosis. Larger studies are warranted to evaluate these effects further.

Original title:
Garlic and Heart Disease by Varshney R and Budoff MJ.

Link:
http://jn.nutrition.org/content/146/2/416S.long

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

Objectives:
Zinc deficiency is a global nutritional problem, particularly in children and women residing in settings where diets are cereal based and monotonous. It has several negative health consequences. Fortification of staple foods with zinc may be an effective strategy for preventing zinc deficiency and improving zinc-related health outcomes. Therefore, this meta-analysis (review article) has been conducted.

What are the beneficial and adverse effects of fortification of staple foods with zinc on health-related outcomes and biomarkers of zinc status in the general population?

Study design:
This review article included 8 RCTs (709 participants); seven were from middle-income countries of Asia, Africa, Europe and Latin America where zinc deficiency is likely to be a public health problem.
The interventions lasted between one and nine months.

Results and conclusions:
The investigators found in 3 studies with 158 participants that foods fortified with zinc increased the serum or plasma zinc levels with 2.12 µmol/L in comparison to foods without added zinc [MD = 2.12 µmol/L, 95% CI = 1.25 to 3.00 µmol/L; low-quality evidence].

The investigators found in 2 studies with 397 participants that participants consuming foods fortified with zinc versus participants consuming the same food without zinc had similar risk of underweight [average risk ratio = 3.10, 95% CI = 0.52 to 18.38; low-quality evidence].

The investigators found in 2 studies with 397 participants that participants consuming foods fortified with zinc versus participants consuming the same food without zinc had similar risk of stunting [RR = 0.88, 95% CI = 0.36 to 2.13; low-quality evidence].

The investigators found no significant difference in serum or plasma zinc levels in participants consuming foods fortified with zinc plus other micronutrients comparing with participants consuming the same foods with micronutrients but no added zinc [MD = 0.03 µmol/L, 95% CI = -0.67 to 0.72 µmol/L; 4 studies of  low-quality evidence with 250 participants].

The investigators found no adverse effect of fortification of foods with zinc on indicators of iron or copper status.

The investigators concluded fortification of foods with zinc may improve the serum zinc status of populations if zinc is the only micronutrient used for fortification. However, when zinc is added to food in combination with other micronutrients, it may make little or no difference to the serum zinc status. Effects of fortification of foods with zinc on other outcomes including zinc deficiency, children's growth, cognition, work capacity of adults or on haematological indicators are unknown. Given the small number of trials and participants in each trial, further investigation of these outcomes is required.

Original title:
Fortification of staple foods with zinc for improving zinc status and other health outcomes in the general population by Shah D, Sachdev HS, […], Peña-Rosas JP.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27281654

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

Objectives:
Anemia is a leading cause of maternal deaths and adverse pregnancy outcomes in developing countries. To present knowledge, no previous study has estimated the population-attributable fraction (PAF) of adverse pregnancy outcomes for maternal anemia. Therefore, this meta-analysis (review article) has been conducted.

Is there an association between maternal anemia and pregnancy outcomes in low- and middle-income countries?

Study design:
This review article included 24 prospective cohorts and 5 retrospective cohort studies.

The number of subjects per study ranged from 253 to 399,274 with a total of ∼0.72 million pregnant women with a mean age that ranged from 20 to 30 years.

Results and conclusions:
The investigators found overall, 42.7% [95% CI = 37.0% to 48.4%] of women experienced anemia during pregnancy in low- and middle-income countries.

The investigators found pregnant women with anemia had a significant higher risk of 31% for low birth weight [RR = 1.31, 95% CI = 1.13-1.51].

The investigators found pregnant women with anemia had a significant higher risk of 63% for preterm birth [RR = 1.63, 95% CI = 1.33-2.01].

The investigators found pregnant women with anemia had a significant higher risk of 51% for perinatal mortality [RR = 1.51, 95% CI = 1.30-1.76].

The investigators found pregnant women with anemia had a significant higher risk of 172% for neonatal mortality [RR = 2.72, 95% CI = 1.19-6.25].

The investigators found South Asian, African and low-income countries had a higher pooled anemia prevalence than did other Asian and upper-middle-income countries.

The investigators found in low- and middle-income countries, 12% of low birth weight, 19% of preterm births and 18% of perinatal mortality were attributable to maternal anemia.

The investigators concluded maternal anemia is a risk factor for adverse birth and perinatal health outcomes in low- and middle-income countries. Significantly higher risk of low birth weight and preterm birth were observed in low-income countries and in South Asian countries despite the greater priority and larger investment on maternal and child health programs in recent decades.

Original title:
Maternal anemia and risk of adverse birth and health outcomes in low- and middle-income countries: systematic review and meta-analysis by Rahman MM, Abe SK, […], Shibuya K.

Link:
http://ajcn.nutrition.org/content/103/2/495.long

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