Determining calcium and vitamin D intakes of female university students, and how they compare to recommendations and intakes from the National Diet and Nutrition Survey.

Abstract

Background: Calcium and vitamin D are vital nutrients to bone health, playing important structural role in bone and vitamin D supporting efficient calcium absorption. Sufficient intakes of these nutrients are required for development and maintenance of bone density. Low intakes of calcium or vitamin D causes reduced bone mineralisation eventually leading to ill-health, in the form of rickets among children, osteomalacia among adults and osteoporosis among the elderly. Vitamin D is primarily obtained from the action of sunlight on human skin. Vitamin D insufficiency is common in the UK due to the lack of dietary sources and the limited sun exposure of the population, increasing the risk of low bone density, and therefore disease, in this population. Aim: The aim of the present study was to determine dietary calcium and vitamin D intakes among a cohort of female university students in Scotland, and to compare these intakes with current dietary reference values and the findings from the National Diet and Nutrition Survey. Method: This study assessed dietary intakes using a 4 day estimated diet diary, where 3 days were required to be weekdays and 1 day a weekend day, as in the National Diet and Nutrition Survey. Intakes reported by participants were analysed using Netwisp nutritional analysis software. Independent t-tests were carried out using SPSS to establish any differences between the present study, the dietary reference values and the National Diet and Nutrition Survey. Results: The sample size was 14. Mean (±SD) calcium intake was 704mg (±284), which was not significantly different from the dietary reference value, nor the National Diet and Nutrition Survey. No participants reported calcium supplementation. Mean (±SD) vitamin D was 1.8ìg (±1.2) from diet alone, and 6.5ìg (±12.8) for diet plus supplement intake. 4 participants reported vitamin D supplementation. Both means were significantly lower than the recommended 10ìg. Results from the National Diet and Nutrition Survey were found to be significantly higher than the mean for diet alone, but significantly lower than the mean for diet plus supplement intake. Conclusion: The present study noted good intakes of calcium, but low intakes of vitamin D among female university students. Poor vitamin D status was also reported in the National Diet and Nutrition Survey and is commonly indicated in the literature. With no recommended intakes for vitamin D for healthy adults improving intakes across the population is difficult. The introduction of a dietary reference value for this nutrient may be necessary, alongside supplementation for at risk groups of the population. Public health messages providing information on vitamin D and safe sun exposure practices may also be beneficial in increasing the vitamin D status of the nation. Keywords: calcium, vitamin D, females, DRV, NDNS, sun exposure.