What is the Metabolic Winter Hypothesis?

The "Metabolic Winter Hypothesis" suggests that in ancient times, humans consistently experienced conditions of cold and hunger, scenarios that are rare in modern life. This hypothesis, coined by David Sinclair and Ray Cronus, revolves around the idea that lack of exposure to cold could be a contributor to current obesity rates. The concept infers that when the body is cold, it must burn more energy to maintain body temperature, which could contribute to better overall energy expenditure and metabolic health.

Challenging the body's system to thermoregulate by inducing colder conditions, such as sleeping in cooler temperatures or minimizing heavily insulated clothing, is considered a way to mimic these ancient conditions. This passive cold exposure, although moderate, can lead to increased energy expenditure over time, highlighting the link between thermal environment and metabolic health 1.