A randomized trial of cold-exposure on energy expenditure and supraclavicular brown adipose tissue volume in humans

Metabolism. 2016 Jun;65(6):926-34. doi: 10.1016/j.metabol.2016.03.012. Epub 2016 Apr 1.

Abstract

Objective: To study if repeated cold-exposure increases metabolic rate and/or brown adipose tissue (BAT) volume in humans when compared with avoiding to freeze.

Design: Randomized, open, parallel-group trial.

Methods: Healthy non-selected participants were randomized to achieve cold-exposure 1hour/day, or to avoid any sense of feeling cold, for 6weeks. Metabolic rate (MR) was measured by indirect calorimetry before and after acute cold-exposure with cold vests and ingestion of cold water. The BAT volumes in the supraclavicular region were measured with magnetic resonance imaging (MRI).

Results: Twenty-eight participants were recruited, 12 were allocated to controls and 16 to cold-exposure. Two participants in the cold group dropped out and one was excluded. Both the non-stimulated and the cold-stimulated MR were lowered within the group randomized to avoid cold (MR at room temperature from 1841±199 kCal/24h to 1795±213 kCal/24h, p=0.047 cold-activated MR from 1900±150 kCal/24h to 1793±215 kCal/24h, p=0.028). There was a trend towards increased MR at room temperature following the intervention in the cold-group (p=0.052). The difference between MR changes by the interventions between groups was statistically significant (p=0.008 at room temperature, p=0.032 after cold-activation). In an on-treatment analysis after exclusion of two participants that reported ≥8days without cold-exposure, supraclavicular BAT volume had increased in the cold-exposure group (from 0.0175±0.015l to 0.0216±0.014l, p=0.049).

Conclusions: We found evidence for plasticity in metabolic rate by avoiding to freeze compared with cold-exposure in a randomized setting in non-selected humans.

Keywords: Brown adipose tissue; Cold exposure; Magnetic resonance imaging; Metabolic rate.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adipose Tissue, Brown / diagnostic imaging*
  • Adipose Tissue, Brown / metabolism*
  • Adult
  • Calorimetry, Indirect
  • Cold Temperature*
  • Energy Metabolism / physiology*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Organ Size / physiology
  • Thermogenesis / physiology*
  • Young Adult