Research

Energy balance

Obese individuals with a 'thrifty' phenotype, characterized by a large decrease in 24-hour energy expenditure during fasting and a small increase during overfeeding, lose significantly less weight during caloric restriction than those with a 'spendthrift' phenotype.

If you are struggling to lose weight despite strict adherence to a calorie deficit, your body may have a 'thrifty' metabolic phenotype that aggressively reduces energy expenditure. This is a biological reality, not a personal failure. Understanding this can help manage expectations and prevent discouragement, as standard caloric deficits may yield smaller results for you than for others.

ModerateQualifiesMEDIUM confidence
We found that a smaller reduction in 24-h energy expenditure during fasting and a larger response to overfeeding predicted more weight loss over 6 weeks... Greater decreases in energy expenditure during caloric restriction predict less weight loss, indicating the presence of thrifty and spendthrift phenotypes in obese humans.
Martin Reinhardt et al. · Diabetes · 2015

Why this rating

Small sample size (n=12) and single-center inpatient study, though methodology is rigorous.

Source

A Human Thrifty Phenotype Associated With Less Weight Loss During Caloric Restriction

Martin Reinhardt et al. · Diabetes · 2015

DOI 10.2337/db14-1881

clinical_trial · n=12Cited 90×
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DOI resolved against Crossref · corpus check 2026-06-10

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