Background/objectives: Low serum 25-hydroxyvitamin D (25(OH)D) concentrations are related to increased mortality. One possible explanation could be an association between serum 25(OH)D and serum lipids.
Subjects/methods: The study was performed at the University of Tromsø, Northern Norway. In total, 8018 nonsmoking and 2087 smoking subjects were included in a cross-sectional study performed in 2008, and 1762 nonsmoking and 397 smoking subjects in a longitudinal study from 1994/1995 to 2008. Nonfasting serum 25(OH)D, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), LDL-C/HDL-C ratio and triacylglycerol (TAG) were measured.
Results: After adjustment for gender, age, sample month and body mass index in the cross-sectional study, there was a significant increase in serum TC, HDL-C and LDL-C, and a significant decrease in serum LDL-C/HDL-C ratio and TAG across increasing serum 25(OH)D quartiles. For serum HDL-C and TAG in nonsmokers the differences between the means for the highest and lowest serum 25(OH)D quartiles were 6.0 and 18.5%, respectively. In the longitudinal study, an increase in serum 25(OH)D was associated with a significant decrease in serum TAG.
Conclusions: There is a cross-sectional association between serum 25(OH)D and serum lipids, and a longitudinal association over 14 years between serum 25(OH)D and TAG, which may contribute to explain the relation between low serum 25(OH)D concentrations and mortality.