Research

Hormonal

Long-term calorie restriction in nonobese humans does not produce a sustained increase in serum cortisol, unlike the sustained increase seen in rodents.

Do not worry that long-term calorie restriction will keep your cortisol chronically high. In nonobese individuals, any increase in cortisol is mild and transient, disappearing after the first year. This contrasts with rodent studies where cortisol increases are sustained.

StrongRefutesHIGH confidence
Serum cortisol concentrations were slightly but significantly increased by CR at 1 year only (P = 0.003)... no change in serum cortisol concentration was detected after 2 years of CR.
Luigi Fontana et al. · Aging Cell · 2015

Why this rating

Large, multicenter, randomized controlled trial (CALERIE) with 218 participants and 2-year duration.

Source

Effects of 2‐year calorie restriction on circulating levels of IGF‐1, IGF‐binding proteins and cortisol in nonobese men and women: a randomized clinical trial

Luigi Fontana et al. · Aging Cell · 2015

DOI 10.1111/acel.12400

rct · n=218Cited 172×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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