Trials that tested the effects of cold exposure on body weight and fat loss have reported inconsistent results,[1] and the long-term efficacy of cold exposure interventions on obesity has yet to be established.[2]
Although research to date points toward a lack of efficacy for cold exposure as a stand-alone long-term weight loss intervention, there have been promising results over smaller timescales. In a randomized controlled trial with 51 participants, 2 hours of daily cold exposure at 17°C (63°F) for 6 weeks resulted in increases in energy expenditure, thermogenesis, and brown adipose tissue (BAT) activation that resulted in a significant amount of fat loss compared to the control participants who were not exposed to the cold.[3] Because people with overweight or obesity tend to have lower amounts of BAT[4][5][6][7][8][9] and cold exposure interventions may improve metabolic health through the expansion of BAT stores and increased nonshivering thermogenesis,[1] more research is warranted to determine whether cold exposure could be helpful alongside other interventions that target obesity.