Research

Hormonal

Classifying individuals by a 'leptin phenotype' (relatively high or low leptin for a given body fat percentage) does not predict differential energy expenditure, metabolic adaptation, or susceptibility to weight change in response to caloric restriction or overfeeding.

Do not rely on fasting leptin levels to predict your weight loss success or failure. Whether your leptin is 'high' or 'low' for your body fat percentage does not appear to change how your body responds to dieting or overeating in terms of energy expenditure or weight change. Focus on sustainable caloric deficits and activity rather than hormonal profiling for prediction.

GoodRefutesHIGH confidence
Leptin phenotype did not explain variations in energy expenditure responses either in cross-sectional analyses or in response to acute or prolonged energetic stressors. Moreover, leptin phenotype was not a determinant of weight change in response to energy restriction or surplus, or subsequent weight recovery.
Kaja Falkenhain et al. · American Journal of Physiology-Endocrinology and Metabolism · 2025

Why this rating

Multi-study design with robust methodologies (whole room calorimetry, DLW) and large sample sizes for chronic interventions, though limited by small subgroups for acute female data.

Source

The effect of a leptin phenotype on weight change and energy expenditure responses to acute and prolonged energetic stressors

Kaja Falkenhain et al. · American Journal of Physiology-Endocrinology and Metabolism · 2025

DOI 10.1152/ajpendo.00067.2025

cross_sectional · n=353Cited 2×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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