Obesity is one of the biggest issues facing the Western world with no solution on the horizon. More than 50% of Australian adults are overweight or obese. In comparison to appetite regulation and caloric intake, our current understanding of regulation of energy expenditure (EE) is relatively poor. Even a small increase in EE (2%) could potentially cause weight loss of ~2-3kg per year. Total EE includes voluntary EE (exercise, including fidgeting), diet induced thermogenesis, and resting or basal EE. Resting EE accounts for ~70% of total EE in the average person, and a greater percentage in very sedentary people.

Humans vary widely in their overall EE, and particularly resting EE. Two major contributors to this are brown adipose tissue (BAT) and beige adipocytes (BA). White adipose tissue (WAT) stores calories. In contrast, BAT and BA consume energy and use mitochondrial uncoupling to produce heat instead of ATP. Uncoupling protein 1 (UCP1) regulates this process and provides an excellent marker of BAT and BA. Rothwell and Stock (1979) estimated that 50g of BAT could consume 20% of daily energy expenditure if stimulated. Previously, only infant humans were thought to have BAT, but recent studies have shown that BAT is present and inducible in adults reigniting interest in the field.

This talk will discuss strategies to increase browning of white fat (beiging) and studies to date in humans.