ABSTRACT
CONTEXT: Breast milk composition is influenced by many factors, ranging from maternal nutritional status to infant sex. Previous studies have explored the relationship between maternal body mass index (BMI) and breast milk composition; however, the findings have been inconsistent and controversial. OBJECTIVE: To systematically review the evidence on the association of maternal weight and BMI with breast milk composition. DATA SOURCES: The PubMed and Scopus databases were searched up to May 3, 2023, using the following search strategy: ("maternal weight" OR "maternal BMI" OR "mother's weight" OR "mother's BMI") AND ("maternal milk" OR "human milk" OR "breast milk"). DATA EXTRACTION: A total of 83 publications, involving data from more than 11â310 lactating women, were identified. All extracted data were compiled, compared, and critically analyzed. DATA ANALYSIS: Overall, maternal BMI was associated with higher levels of leptin and insulin, and the ratio of omega-6 to omega-3 polyunsaturated fatty acids in breast milk. However, no conclusive associations were found between maternal BMI and the levels of energy, macronutrients, micronutrients, and other components of breast milk. CONCLUSIONS: This systematic review provides robust evidence supporting a positive correlation between maternal BMI and breast milk concentrations of leptin, insulin, and the omega-6 to omega-3 polyunsaturated fatty acid ratio. Nevertheless, disparities in findings are noticeable for other constituents of breast milk. To comprehensively grasp the influence of maternal weight and BMI on breast milk composition, further research endeavors are imperative. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42023458667.
ABSTRACT
INTRODUCTION: The last decade has seen the increased prevalence of obesity as a public health challenge, particularly in low- and middle-income countries. At the same time, studies have shown that there is a two-way relationship between low-calorie diets and depression in obese individuals. This study was designed and implemented to investigate the effect of a low-calorie high-protein diet on psychometric variables in obese individuals. MATERIALS AND METHODS: The present study is a Randomized Clinical Trial. Individuals meeting the inclusion criteria were randomly assigned to either the intervention group (low-calorie diet with increased protein percentage) or the control group (standard protein percentage) using block stratification. Psychometric characteristics of the participants were evaluated using the DASS-21 questionnaire. RESULTS: There were no significant differences in enrollment between the two groups with respect to anthropometric variables, body composition, and physical activity (p-value > .05). Similarly, no significant differences were observed between the two groups in terms of psychological variables (depression, anxiety and stress) (p-value > .05). However, the intervention groups had significantly lower depression and anxiety scores 15 days into the intervention (p-value < .05). After 30 and 60 days of intervention, significant differences were observed between the 2 groups in terms of depression, stress, and anxiety (p-value < .05), indicating a relative improvement in psychometric variables in the intervention group (p-value < .05). CONCLUSION: The results of this study showed that low-calorie diets with a high-protein percentage can significantly improve psychometric variables in obese people.Trial registration: Iranian Registry of Clinical Trials identifier: IRCT20221101056371N1..