Determinants of serum 25(OH)D concentration in young and middle-aged adults. The Cardiovascular Risk in Young Finns Study

Abstract

Introduction. We studied prevalence of hypovitaminosis D, its determinants, and whether achievement of recommended dietary vitamin D intake (10 μg/d) is associated with absence of hypovitaminosis D in adults.Methods. The study is part of the Cardiovascular Risk in Young Finns Study. We collected serum samples of 25-hydroxyvitamin D as part of the 27-year follow-up (994 men and 1,210 women aged 30–45 years). Hypovitaminosis was defined as vitamin D concentration ≤ 50 nmol/L.Results. Hypovitaminosis D was found in 38% of men and 34% of women. Dietary vitamin D intake (OR 0.90, 95% CI 0.86–0.93), use of vitamin–mineral supplements (0.66, 0.51–0.85), sunny holiday (0.55, 0.41–0.75), and oral contraceptive use in women (0.45, 0.27–0.75) were independently associated with reduced odds of hypovitaminosis. Increase in body mass index (1.06, 1.03–1.09), being a smoker (1.36, 0.97–1.92), investigation month (December versus other) (1.35, 1.12–1.61), and risk alleles in genotypes rs12785878 (1.31, 1.00–1.70) and rs2282679 (2.08, 1.66–2.60) increased odds of hypovitaminosis. Hypovitaminosis D was common also when recommended dietary intake was obtained (men 29%, women 24%).Conclusion. Several factors were associated with hypovitaminosis D. The condition was common even when recommended vitamin D intake was reported. The results support the importance of vitamin D fortification and nutrient supplement use.