The Physiological Effects of Weight-Cycling: A Review of Current Evidence.
Level 3 - non-randomized controlled study
Systematic review of predominantly observational (cross-sectional and cohort) studies and non-RCT interventional designs
PubMed 38172475 · doi:10.1007/s13679-023-00539-8
What was done
A systematic review evaluated the physiological effects of weight-cycling on body weight, BMI, body composition (fat mass and lean body mass), and resting metabolic rate (RMR). The authors included 23 studies (cross-sectional, cohort, and interventional) in generally healthy adults across various age groups, sexes, races, and weight categories (normal weight, overweight, or obesity).
What was found
- Body weight and BMI: 13 of 18 studies found no significant association with weight-cycling. - Fat mass: 15 of 20 studies found no increase. - Lean body mass: 0 of 18 studies found a decrease. - Resting metabolic rate: 12 of 14 studies reported no adverse changes.
Why it matters
This review directly addresses the common belief that yo-yo dieting damages metabolism or increases adiposity, suggesting individuals should not be discouraged from attempting weight loss repeatedly.
Limits
The review combines heterogeneous study designs, including cross-sectional associations that cannot establish causality. The abstract does not report pooled effect sizes, confidence intervals, exact definitions/thresholds used for weight cycling, or risk of bias assessments.
Cited by
- contradicts Studies on yo-yo dieting and prolonged starvation periods show that they lower metabolic rate, which can lead to subsequent weight gain.