Body composition and vitamin D status: the Korea National Health And Nutrition Examination Survey IV (KNHANES IV)

Abstract

The present study aimed to assess the association of total and regional body fat percentage (FP) and lean mass (LM) with vitamin D deficiency {serum 25-hydroxyvitamin D [25(OH)D] <20ngmL(-1) } using the data of the Fourth Korea National Health And Nutrition Examination Survey (KNHANES IV). Subjects were participants of the KNHANES IV conducted in 2009 and were aged ≥19years. In 6791 participants, serum 25(OH)D, body composition [body mass index, waist circumference, and total and regional (trunk and legs) FP and LM by dual energy X-ray absorptiometry] were measured. Confounders (age, residential place, housing status, occupation, smoking, alcohol use, physical activity, medical history and calcium intake per day) were assessed. After adjusting for confounders, vitamin D deficiency was significantly associated with FP with the odds ratios (ORs) from 1.09 to 1.20, and LM with the ORs from 0.81 to 0.87 in men. In men, serum 25(OH)D remained inversely associated with FP tertiles after adjustment for LM, and positively with LM tertiles after adjustment for FP. When FM tertiles and LM tertiles were combined in men, the OR for vitamin D deficiency was 2.2 (P<0.05) in the combined subgroup of highest total FM tertile and lowest total LM tertile compared to the subgroup of lowest total FM tertile and highest total LM tertile. However, these associations were nonsignificant or inconsistent in women. The associations of vitamin D deficiency with body fat and lean mass were significant in Korean men but were inconsistent in Korean women.