Vitamin D Deficiency, Skin Phototype, Sun Index, and Metabolic Risk Among Patients with High Rates of Sun Exposure Living in the Tropics.

We sought to evaluate serum 25-hydroxycholecalciferol (vitamin D [25-OHD]) levels, skin phototype, and sun index in a sample of patients to determine the association between these factors and metabolic risk. This was a cross-sectional study involving 729 adults (50.2% male). Mean age was 65.13±9.18 years, sun index 5.71±5.06, body mass index (BMI) 27.60±5.34 kg/m, and waist circumference 97.29±12.08cm. Hypertension, metabolic syndrome, and Type 2 diabetes were reported in 77.8, 74.5, and 38.9 percent, respectively; Fitzpatrick Skin Types III and IV were reported in 60.6 percent. Mean serum 25-OHD was 25.72±10.91ng/mL; 31 percent of subjects had serum 25-OHD below 20ng/mL, and 63.1 percent had serum 25-OHD below 30ng/mL. Although there were no significant differences between the vitamin D deficient and sufficient groups regarding age, BMI, waist circumference, or presence of diabetes, in the group with 25-OHD less than 20ng/mL (sun index of 4.5±4.08), higher serum triglycerides and lower high-density lipoprotein cholesterol (HDL-C) levels were measured: triglycerides 179.14±103.53 versus 161.63±90.23mg/dL (=0.029) and HDL-C 43.48±12.38 versus 45.94±14.14mg/dL (=0.018) compared to the group with 25-OHD levels of 20ng/mL or higher (sun index: 6.25±5.36). Considering less than 25th percentile (25-OHD: 18.7ng/mL) and 75th percentile or higher (25-OHD: 30.8 ng/mL), the differences in serum triglycerides remained significant: 176.63±103.79 versus 157.47±80.49 (=0.039). We found a high prevalence of vitamin D deficiency in individuals with high sun exposure, regardless of age, BMI, and waist circumference. This deficiency was associated with increased serum triglycerides and decreased HDL-C levels.