Association of calcium intake, lactose intolerance and physical activity with bone health assessed via quantitative ultrasound among young adults of a Malaysian university

Lactose intolerance has been proposed to cause poor bone health. This study found the prevalence of lactose intolerance was high among Malaysian young adults, but not associated with bone health status, unlike calcium intake. This is the first study that investigated the association of lactose intolerance and bone health status in Malaysia.

PURPOSE: The aims of this study were to determine the prevalence of lactose intolerance, calcium intake and physical activity level and to investigate the association between these variables with bone health status among young adults.

METHODS: This cross-sectional study consisted of 300 Malay, Chinese and Indian students from Universiti Kebangsaan Malaysia with mean age of 22.5 ± 3.2 years. Determination of lactose tolerance status was performed using hydrogen breath test, lactose tolerance test and visual analogue scales. Calcium intake and physical activity level were evaluated using Food Frequency Questionnaire and International Physical Activity Questionnaire, respectively. Bone health status was assessed on calcaneal bone, using quantitative ultrasound.

RESULTS: Lactose intolerance was highly reported among the Malay subjects (72%) followed by Chinese (59%) and Indians (42%). The mean calcium intake was 542.9 ± 365.2 mg/day whilst the mean physical activity was 2757.6 ± 2007.2 MET-min/week. The bone assessment showed that 91% of the subjects had a low risk of developing osteoporosis. Only calcium intake showed a significant association with bone health status (β = 0.006; p = 0.033), whilst no association was shown for lactose intolerance and physical activity level.

CONCLUSIONS: Malaysian young adults showed a high prevalence of lactose intolerance. Calcium intake is associated with increased bone health status. In contrast, lactose intolerance and physical activity level did not directly influence bone health status. Nutrition education promoting adequate calcium intake should be implemented among young adults due to high lactose intolerance prevalence and low calcium intake among subjects.