Increase in skimmed milk intakes brings positive calcium balances during body weight reduction by exercise

Abstract

Suitable diets during body weight‐loss programs are not understood in detail. We investigated the effects of increasing skimmed milk intakes on nutritional status and metabolism of calcium and magnesium.MethodsSix adult male volunteers participated in crossover trial, i.e., two experiments over eight days. The first four days were an adjustment period consuming control diets (energy, 2,553 kcal; calcium, 1,028 mg; magnesium, 343 mg; mean intake levels per day). During the second four days, the participants exercised on a bicycle ergometer (mean additional energy, 511 kcal per day), and consumed either control diets or experimental diets which contained increased skimmed milk but the same energy levels as control diets.ResultsAlthough urinary and fecal calcium excretion levels were higher, calcium balances were significantly more positive during experimental period than during control period. Whereas magnesium balances during increased skimmed milk intakes are almost the same as during control diets. On the other hand, no significant differences in serum calcium, magnesium and intact parathyroid hormone (PTH) levels were observed between two diet methods.ConclusionsIncrease in skimmed milk intakes brings positive calcium balances during body weight reduction by exercise, but the regulation of calcium by PTH is not clear. This study was supported by a grant from Kanto Gakuin University.