Cold exposure triggers the release of norepinephrine in the brain and body, which can convert white fat cells to beige and brown fat. Neurons in the skin sense cold and can directly release norepinephrine into fat stores, causing these changes. Deliberate cold exposure can have positive biological effects on brain biology, metabolism, and brown fat thermogenesis. It can also be healthy for sperm quality by reducing heat. When we talk about deliberate cold exposure, it means getting uncomfortable and placing yourself into a cold environment on purpose to extract a particular set of benefits.