Embodiments of the disclosure concern methods and compositions that relate to increasing or decreasing the weight (including, for example, by increasing or decreasing the adipose mass) in individuals in need thereof. Such methods and compositions, in particular embodiments, concern providing an effective amount of the hormone asprosin to increase adipose mass in an individual with insufficient adipose mass and providing an antibody or inhibitor of asprosin in an individual with obesity or diabetes, for example, to reduce adipose mass.