Effects of calcium-fortified ice cream on markers of bone health

Abstract

Premenopausal women with low calcium intakes consumed calcium-fortified ice cream daily for 28days. Bone markers, NTX, CTX and PTH decreased significantly by 7days, with some evidence of a calcium dose-dependent effect. Bone marker responses were observed within 1h of consuming ice cream. Body weight remained constant over 28days. Dietary calcium is important for lifelong bone health. Milk is a good source of bioavailable calcium, but consumption has declined among young adults. The aims were to determine whether calcium-fortified ice cream, a palatable source of calcium, produces significant, sustainable changes in bone turnover markers and parathyroid hormone (PTH) in premenopausal women with calcium intake below recommended UK levels. Eighty women, ages 20-39years (calcium intake <750mg/day) were randomised to consume lower saturated fat/sugar ice cream containing 96, 244, 459 or 676mg calcium daily for 28days. Urinary NTX/Cr, serum CTX, PINP, 1,25D and PTH were measured (baseline, days1, 7 and 28). Acute changes in CTX and PTH were measured over 5h (n = 29 women). There were significant mean decreases by 7days in NTX/Cr, CTX, PTH and 1,25D and increases in PINP (one sample t tests), with a significant dose-dependent effect on CTX analysis of covariance. Only CTX remained suppressed at 28days. Serum CTX and PTH decreased within 1h. Body weight did not change significantly between baseline and 28days. Daily consumption of calcium-fortified ice cream by premenopausal women may significantly reduce levels of the bone resorption marker serum CTX, without stimulating weight gain. The ice cream could be incorporated into the diet to replace low-calcium snacks and thus help individuals with habitually low calcium intakes to meet recommended intakes. The 244mg calcium preparation would provide more than a quarter of the UK daily recommended nutrient intake for premenopausal women.