Abstract: Fasting improves metabolic health, but rapid weight gain after fasting might have a neg. impact on health. We investigated whether repeated bouts of fasting and refeeding promote accumulation of body fat and protect skeletal muscle as well as liver from wasting during the subsequent exposure to fasting. We compared changes in body composition after the first bout (bout 1) and the eighth bout (bout 8) of 2-day fasting followed by 5-day re-feeding in 22-wk-old C57BL/6J male mice. We have also assessed serum IGF-1 and gene expression of proteasome (MurF1, Atrogin-1) and autophagy (p62, LC3b) markers of protein breakdown in skeletal muscles and liver. In contradiction to our expectations, weight- and aged-matched mice showed slightly greater weight loss in bout 8 compared bout 1 of fasting (17.6 ± 2.2 vs. 15.2 ± 2.4 %, n = 10, p < 0.05). Skeletal muscles showed significant upregulation of proteasome and autophagy markers, but only small loss of mass. Liver wasting was significant even though upregulation of autophagy gene expression was modest compared to skeletal muscles. Serum IGF-1 increased and was associated with significant increase in mass of gonadal white adipose tissue. In summary, repeated bouts of fasting and refeeding lead to high serum IGF-1 levels and promote accumulation of body fat, but does not protect from loss of lean body mass during fasting.