Predictors of vitamin D biochemical status in a large sample of middle-aged male smokers in Finland

Eur J Clin Nutr. 2010 Mar;64(3):280-8. doi: 10.1038/ejcn.2009.137. Epub 2010 Jan 6.


Background/objectives: As vitamin D deficiency is considered to be more common in regions with little solar ultraviolet (UV) light in winter, the aim of this study was to analyze predictors of vitamin D status by season within a large sample of male smokers from Finland, a country where there is negligible solar UV light in winter.

Subjects/methods: Vitamin D (measured by 25-hydroxyvitamin D (25(OH)D) nmol/l) and other serum constituents were assayed. Measured anthropometry, and self-reported dietary intake and physical activity (PA) were obtained and analyzed using stepwise multiple linear and logistic regression in 2271 middle-aged Finnish male smokers.

Results: In all, 27% of the population in winter and 17% in summer had serum 25(OH)D levels of <25 nmol/l, respectively. In summer, in multiple logistic regression analyses with adjustment for confounding and other predictors, high vitamin D intake (odds ratios (OR) 3.6; 95% confidence interval (CI) 1.5-8.5), some leisure time PA (OR 2.0; 95% CI 1.3-3.1) and having a body mass index (BMI) of >or=21 kg/m(2) compared with <21 kg/m(2) (OR 2.6; 95% CI 1.3-5.0), were associated with 25(OH)D >or=25 nmol/l. In winter, additional modifiable factors were occupational PA (OR 1.6; 95% CI 1.1-2.5) and high fish (OR 3.1; 95% CI 1.7-6.2) or poultry consumption (OR 1.7; 95% CI 1.2-2.5). Predictors from linear regression analyses of continuous levels of 25(OH)D were similar to the logistic regression analyses of 25(OH)D >or=25 nmol/l.

Conclusion: In this Finnish sample more vitamin D intake, PA and having a BMI of >or=21 may have important modifiable roles in maintaining an adequate vitamin D status.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Aged
  • Body Mass Index
  • Cross-Sectional Studies
  • Exercise / physiology
  • Finland
  • Humans
  • Linear Models
  • Logistic Models
  • Male
  • Middle Aged
  • Nutritional Status*
  • Predictive Value of Tests
  • Randomized Controlled Trials as Topic
  • Risk Factors
  • Seafood
  • Seasons
  • Smoking / blood*
  • Ultraviolet Rays*
  • Vitamin D / administration & dosage
  • Vitamin D / biosynthesis
  • Vitamin D / blood*
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / epidemiology*


  • Vitamin D