The aim of the present prospective study over a follow-up period of two years was to assess the influence of various doses of glucocorticosteroids on the total body fat and lean tissue masses and their regional distribution, using DXA technique, in twenty-four patients with giant cell arteritis (GCA). Treatment with glucocorticoids for two years, using high doses of prednisolone the first six months and lower doses thereafter, resulted in a significant increase in total body fat as well as in trunk fat expressed either as absolute values or as a proportion of body weight. The abnormal accumulation of fat mass remained also after switching to a low dose glucocorticoid schedule. There was no redistribution of fat from peripheral areas to central parts of the body and there was no depletion of lean tissue at peripheral sites.