What are the benefits of cold exposure?

Cold exposure may boost metabolism, mood, focus, resilience, and thermogenic fat activity, and may reduce inflammation.

• Metabolism and brown fat: Repeated cold exposure can increase brown-fat activation and thermogenesis, supporting heat production and making people more comfortable in cold. It may also raise metabolism, in part by promoting changes from energy-storing white fat toward beige or brown fat. 1 2
• Dopamine, mood, and focus: In a study of prolonged cool-water immersion, dopamine rose by about 250% and remained elevated after exposure; Huberman connects these catecholamine increases with improved mood, energy, alertness, and mental focus. 3 4
• Thermogenic fat and inflammation: Cold can encourage white fat to become more metabolically active beige or brown fat. Cold exposure is also used to reduce inflammation, including after exercise; a winter-swimming study discussed in the episode found lower blood pressure and heart rate, which Søberg suggested could relate to reduced inflammation. 5 6 7
• Stress resilience and eustress: Deliberate cold can be a controllable stressor for practicing resilience. Huberman describes it as potentially producing “eustress”—increases in catecholamines without a significant cortisol increase in the study discussed. 8 9
• Hormones and fertility-related effects: One study discussed in the show found increased testosterone and free testosterone in men and women, and improved sexual satisfaction among participants exposed to cold; the proposed link to sexual satisfaction was presented as a possibility, not a proven cause. 10
• Safe progression: Start gradually and choose an exposure that is uncomfortable but safe; extreme cold can cause cold shock and be dangerous. Consistency and safety are emphasized over rigid targets. 11 12