Research

Hormonal

Long-term mild cold exposure (19°C overnight for 1 month) reversibly increases brown adipose tissue (BAT) abundance and activity, which enhances postprandial insulin sensitivity and diet-induced thermogenesis in healthy adult men.

For healthy young men, sleeping in a cooler room (around 19°C or 66°F) for several weeks may help improve how your body handles sugar after meals by activating brown fat. This is not a weight-loss strategy, as body weight did not change, but it may support metabolic health. It requires consistent nightly exposure, not just occasional cold showers.

ModerateSupportsMEDIUM confidence
Sequential monthly acclimation modulated BAT reversibly, boosting and suppressing its abundance and activity in mild cold and warm conditions (P < 0.05)... BAT acclimation did not alter CIT but was accompanied by DIT (P < 0.05) and postprandial insulin sensitivity enhancement (P < 0.05), evident only after cold acclimation.
Paul Lee et al. · Diabetes · 2014

Why this rating

Small sample size (n=5), short duration (4 months), and lack of long-term health outcome data limit generalizability.

Source

Temperature-Acclimated Brown Adipose Tissue Modulates Insulin Sensitivity in Humans

Paul Lee et al. · Diabetes · 2014

DOI 10.2337/db14-0513

crossover · n=5Cited 394×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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