Protein supplementation in women
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Protein Supplementation and Body Composition in Women
Research shows that whey protein supplementation can modestly increase lean mass in women, but it does not significantly affect fat mass. The effect is more pronounced when whey protein is combined with energy restriction, while the benefit is less clear when combined with resistance training alone or without energy restriction 1. In postmenopausal women, whey protein supplementation only improves muscle strength and lower limb lean mass when combined with resistance training; without exercise, there is no significant benefit on muscle strength or lean mass, and no effect on fat mass or body weight loss 2.
Protein Supplementation in Older and Postmenopausal Women
Long-term whey protein supplementation in well-nourished, healthy older postmenopausal women does not enhance muscle mass or physical function, even with increased protein intake 7. However, expert consensus recommends that postmenopausal women consume 1.0–1.2 g/kg body weight of high-quality protein daily, ideally with 20–25 g at each main meal, and combine this with regular physical activity to help maintain musculoskeletal health and prevent age-related muscle and bone loss 8. Evidence also suggests that both whey and soy protein may provide some benefit to muscle strength, but the overall quality of evidence is limited 9.
Protein Supplementation and Birth Outcomes in Pregnant Women
Balanced protein-energy supplementation during pregnancy is effective in improving birth outcomes, especially in undernourished women. It increases birthweight and birth length, and reduces the risk of low birth weight and small-for-gestational-age babies, with a more pronounced effect in women who are undernourished 35. However, there is no significant effect on head circumference, perinatal death, or preterm birth 3.
Protein Supplementation in Special Populations
Among women living with HIV/AIDS, protein supplementation and nutrition education both significantly increase lean mass and total weight, suggesting that nutritional interventions can improve body composition and health outcomes in this population 6.
Types of Protein Supplements and Their Effects
Different protein sources, such as meat, vegan, branched-chain amino acids (BCAAs), and whey, have been studied in young women practicing resistance exercise. BCAAs and vegan supplements were associated with a decrease in body weight and BMI, but no significant differences were observed in muscle mass gains between the different protein types over an eight-week period. Longer interventions may be needed to see clearer effects 4.
Soy Protein Supplementation and Menopausal Symptoms
Soy protein supplementation in perimenopausal women can significantly lower total and LDL cholesterol, reduce diastolic blood pressure, and improve the severity of vasomotor and hypoestrogenic symptoms, supporting its potential role in reducing chronic disease risk and improving quality of life during menopause 10.
Conclusion
Protein supplementation in women can offer modest benefits for lean mass, especially when combined with energy restriction or resistance training. In postmenopausal women, the combination of protein intake and exercise is key for muscle health, while in pregnant and undernourished women, balanced protein-energy supplementation improves birth outcomes. The type of protein supplement may influence body composition, but more research is needed for clear recommendations. For menopausal symptoms and cardiovascular health, soy protein shows additional benefits. Overall, protein supplementation should be tailored to individual needs, life stages, and combined with other healthy lifestyle practices for optimal results.
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