Betaine supplementation fails to improve body composition: a systematic review and meta-analysis

Abstract

Previous studies evaluating the effects of betaine supplementation on body composition offer contradictory findings. This systematic review and meta-analysis assessed the effects of betaine supplementation on body composition indices (body mass [BM], body mass index [BMI], body fat percentage [BFP], fat mass [FM], fat-free mass [FFM]), and dietary intakes. Studies examining the effects of betaine supplementation on body composition and dietary intakes published up to August 2021 were identified through PubMed, the Cochrane Library, Web of Science, Embase, SCOPUS, and Ovid databases. Betaine supplementation failed to significantly affect BM [(WMD: −0.40 kg, 95% CI: −1.46 to 0.64), p=0.447], BMI [(WMD: −0.05 kg/m2, 95% CI: −0.36 to 0.25), p=0.719], BFP [(WMD: 0.26%, 95% CI: −0.82 to 1.36), p=0.663], FM [(WMD: −0.57 kg, 95% CI: −2.14 to 0.99), p=0.473], and FFM [(WMD: 0.61 kg, 95% CI: −1.27 to 2.49), p=0.527]. Subgroup analyses based on participant’s age (<40 and >40 years), sex, BMI, trial duration (<8 and ≥8 weeks), betaine supplementation dosage (<4 and ≥4 g), and health status (healthy or unhealthy) demonstrated similar results. Other than a potential negligible increase in protein intake (WMD: 3.56 g, 95% CI: 0.24 to 6.88, p=0.035), no changes in dietary intakes were observed following betaine supplementation compared to control. The present systematic review and meta-analysis does not show any beneficial effects of betaine supplementation on body composition indices (BM, BMI, FM, and FFM).

Betaine as a Functional Ingredient: Metabolism, Health-Promoting Attributes, Food Sources, Applications and Analysis Methods

“…After a fourteen-week period, biochemical analyses revealed increased testosterone levels in supplemented individuals, while there were no significant changes in lean body mass or body fat. According to a meta-analysis by Ashtary-Larky et al [ 98 ], betaine supplementation does not improve body composition. No significant changes in body composition indices, such as body mass, body mass index, body fat percentage, fat mass, or fat-free mass, were noted.…”

Betaine and Soluble Fiber Improve Body Composition and Plasma Metabolites in Cats with Chronic Kidney Disease

“…Also, a study of men in a strength training program found that betaine supplementation for 6 weeks improved body composition by lowering body fat and fat mass and increasing lean body mass compared with placebo [30]. However, meta-analyses of clinical trials in humans found that dietary betaine supplementation did not affect body mass [31,32], similar to healthy cats [23]. Body fat was lowered with betaine supplementation [32], so the effects of betaine on body mass may depend on the species, kidney function status, and/or high metabolic demand.…”