Beige fat, a newly discovered adipose tissue featuring high functional flexibility, exhibits the characteristics of white fat at rest, but can be activated to function like brown fat under cold or β-adrenergic stimulation via a process termed ‘browning of white fat’. This activation enables beige fat to greatly promote heat production and energy consumption, as well as to improve systemic glucose and lipid metabolism. Beige fat also exists in supraclavicular and paraspinal regions in human adults, which endows its great potential for intervention of obesity and metabolic diseases.