Dietary Intake of Animal and Plant‐Based Protein on Adiposity Measurements and Body Composition in Pre‐ and Postmenopausal Women: A Systematic Review of Randomized Clinical Trials

ABSTRACT

This systematic review investigated the effect of protein intake on anthropometric and body composition markers in pre‐ to postmenopausal women. Understanding these effects may contribute to the development of nutritional strategies to improve body composition and prevent changes associated with this phase. Searches were conducted in the PubMed, EMBASE, and Cochrane Library databases, following the PRISMA guidelines, and the risk of bias was assessed using the Joanna Briggs Institute (JBI) tool (PROSPERO: CRD420251156313). Fifteen randomized clinical trials, involving 1161 pre‐ and postmenopausal women, were included. Interventions with animal‐based protein ( n  = 8) showed more consistent effects on weight and body fat reduction, especially when combined with calorie restriction and supervised exercise. Protocols using whey protein, meat, or milk protein demonstrated reductions in body fat over 8–16 weeks, with increases in lean mass in longer interventions. However, these effects are strongly influenced by the use of other strategies, such as energy restriction and physical exercise. Studies with soy protein isolate ( n  = 7) showed more heterogeneous results, with few changes in short‐term interventions and more favorable results when combined with exercise. When analyzed independently of energy restriction and physical exercise, the effects of consuming both proteins on body composition were less consistent, making it impossible to confirm benefits from an isolated increase in protein intake. Animal proteins have more consistent effects on anthropometric markers and body composition in women during the climacteric period, particularly when combined with energy restriction and physical exercise. In contrast, plant‐based proteins have more heterogeneous effects, with greater benefits observed when associated with exercise. The findings of this review reinforce the importance of considering protein type, dose, duration of intervention, and other combined strategies when developing nutritional recommendations for changes in body composition.