Purpose of review: Brown adipose tissue (BAT) was thought to be a tissue with physiological importance early in life (maintenance of body temperature) and to disappear after birth. Recent studies using functional imaging have identified the presence of BAT activity throughout life. This review focuses on the effect of age on BAT function as well as BAT as a potential therapeutic target against age-related metabolic diseases.
Recent findings: The PET/computed tomography method likely underestimates the prevalence of BAT because it measures only active BAT. The factors underlying the decline of BAT activity with age are currently unknown, but likely associated with changes in the activity of the sympathetic nervous system and the thyroid axis. Apart from age, the presence of active BAT is decreased in males and overweight. The developmental origins of brown adipose depots as well as transcription factors involved in their differentiation have recently been described. Data suggest that BAT may be recruited throughout life.
Summary: New imaging techniques may provide more accurate estimations of BAT mass in adults. Given its high metabolic rate, it is suggested that BAT mass and activity could be activated and thus represent a potential target for the management of body weight.