Research

Energy balance

A 1-month very-low-calorie ketogenic diet (VLCKD) in women with obesity causes a significant reduction in 24-hour energy expenditure (24hEE) and sleeping metabolic rate (SMR), primarily driven by the loss of lean soft tissue (LST) rather than metabolic adaptation alone.

If you follow a very-low-calorie ketogenic diet, expect your daily calorie burn to drop by about 10% after a month. This isn't just 'metabolic damage'; it's largely because you are lighter and have lost some muscle. To protect your metabolism, prioritize the protein target (1.2-1.5g/kg ideal body weight) and incorporate light resistance or walking to preserve lean tissue.

GoodSupportsHIGH confidence
A 10% decrease in 24hEE and 24-hour sleeping metabolic rate was observed at V3 compared with V1... These findings suggest that the observed reduction in EE at V3 was primarily driven by the decrease in LST.
Alessio Basolo et al. · The Journal of Clinical Endocrinology & Metabolism · 2025

Why this rating

Prospective outpatient study with metabolic chamber measurements (gold standard for EE) but small sample size (n=17) and lack of randomization.

Source

Effects of 1-Month Very-Low-Calorie Ketogenic Diet on 24-Hour Energy Metabolism and Body Composition in Women With Obesity

Alessio Basolo et al. · The Journal of Clinical Endocrinology & Metabolism · 2025

DOI 10.1210/clinem/dgaf196

cohort · n=39Cited 3×
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DOI resolved against Crossref · corpus check 2026-06-10

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