Research

Hormonal

Post-obese individuals who have successfully lost weight exhibit significantly lower plasma leptin concentrations and lower rates of fat oxidation (higher respiratory quotient) compared to never-obese controls matched for body mass index and body fat percentage.

If you have lost weight and maintained it, your body may still be biologically primed to regain it through lower fat burning and lower leptin levels, even if you look healthy. This is a common biological adaptation, not a failure. To counter this, focus on strategies that increase fat oxidation, such as regular exercise and potentially adjusting fat intake, as suggested by the authors.

ModerateSupportsMEDIUM confidence
post-obese subjects had, compared with controls, similar levels of physical activity... and similar RMR... but higher RQ... Leptin concentration correlated positively with percent body fat... and, after adjusting for fat mass and fat-free mass, was lower in post-obese than in control subjects
Claudia Filozof et al. · Obesity Research · 2000

Why this rating

Small sample size (n=16) and cross-sectional design limit generalizability, though the controlled conditions (weight stability, standardized diet) strengthen internal validity.

Source

Low Plasma Leptin Concentration and Low Rates of Fat Oxidation in Weight‐Stable Post‐Obese Subjects

Claudia Filozof et al. · Obesity Research · 2000

DOI 10.1038/oby.2000.23

cross_sectional · n=16Cited 78×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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