Serum 25(OH)D deficiency is becoming an epidemic. The aim was to assess vitamin D status of the adult Greek population in relation to intake, sun exposure and other factors, using data from the Hellenic National Nutrition and Health Survey (HNNHS).

Data from 1084 adult participants (37.8% males) were analyzed. Vitamin D intake was assessed using 24-h recalls. Serum 25(OH)D concentration was evaluated and related to anthropometric measurements and other covariates including supplements used, by sex. Variables significantly associated with 25(OH)D < 20 ng/ml were assessed using simple and multiple logistic regression.

Median vitamin D intake from food was 1.23 mcg/day (0.60, 2.44), with 9.1% consuming supplements. Median serum 25(OH)D was 16.72 ng/ml, with no sex differences (P = 0.923). The odds of having 25(OH)D < 20 ng/ml significantly decreased with being very active (OR 0.55, 95% CI 0.35, 0.98), increasing length of sun exposure [1–3 h/day (OR 0.59, 95% CI 0.44, 0.80), >3 h/day (OR 0.36, 95% CI 0.24, 0.55)], and skin colour [light to medium skin (OR 0.47, 95% CI 0.24, 0.91), fairly dark skin colour (OR 0.34, 95% CI 0.17, 0.67) and dark or very dark skin colour (OR 0.34, 95% CI 0.15, 0.75)], compared to respective baseline levels. The odds significantly increased with obesity (OR 1.95, 95% CI 1.24, 3.08), and spring season of blood sample collection (OR 1.75, 95% CI 1.22, 2.50).

Vitamin D deficiency is highly prevalent in Greek adults. Relevant public health policies are highly recommended, which could include vitamin D fortification. and suggestion for increased but safe sun exposure.