Research

Energy balance

Exposure to mild cold (16°C) activates brown adipose tissue (BAT) in healthy adult men, leading to increased energy expenditure and contributing to adaptive thermogenesis.

You likely have active brown fat, even if you are overweight. Exposing yourself to mild cold (around 60°F/16°C) for about two hours can activate this tissue and burn more calories. This is not about shivering or extreme cold, but a gentle, sustained coolness that your body can handle.

GoodSupportsHIGH confidence
Brown-adipose-tissue activity was observed in 23 of the 24 subjects (96%) during cold exposure but not under thermoneutral conditions... The resting metabolic rate adjusted for fat-free mass... increased significantly during exposure to cold in both groups (P<0.001 for both comparisons)
Wouter D. van Marken Lichtenbelt et al. · New England Journal of Medicine · 2009

Why this rating

High-quality study design (PET-CT, controlled environment, clear inclusion criteria), but small sample size (n=24).

Source

Cold-Activated Brown Adipose Tissue in Healthy Men

Wouter D. van Marken Lichtenbelt et al. · New England Journal of Medicine · 2009

DOI 10.1056/nejmoa0808718

cross_sectional · n=24Cited 3,437×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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