Higher intakes of dietary caffeine are associated with 25-hydroxyvitamin D deficiency: a study from the NHANES
Fang Yanga Nutrition Available online 2 June 2021, 111380
Background & Aims
Low serum 25-hydroxyvitamin D [25(OH)D] levels are a global concern. A couple of in vitro studies observed a decrease in the expression of vitamin D receptor induced by caffeine, but there is a scarcity of research to define the extent of caffeine intake on 25(OH)D levels. Thus, we aimed to associate dietary caffeine intake with 25(OH)D deficiency through a recognized dataset.
Methods
Using data collected from the 2005–2006 National Health and Nutrition Examination Survey (NHANES), 25(OH)D levels and dietary caffeine intake were extracted. We used one-way ANOVA and Chi-square tests for quantitative and qualitative variables, respectively, and performed multivariate logistic regression for four models to assess the odds ratio (OR) of 25(OH)D deficiency (<20 ng/ml or <50 nmol/L) based on quartiles of dietary caffeine intake.
Results
Addressing a sample size of 13134 individuals in the NHANES dataset, whose population consisted of young and middle-aged adults (30–47 years, interquartile range) in general, both crude and multivariable models detected higher OR for 25(OH)D deficiency according to the highest intakes of caffeine (15.8 ± 9.50, 51.9 ± 11.9, and 177 ± 156 mg/d) when compared to the reference category (2.19 ± 1.04 mg/d). In this way, the OR for the highest category of caffeine intake was 1.24 (95% CI: 1.12 to 1.37) and 1.48 (95% CI: 1.16 to 1.78) for the crude model and the most complete multivariable analysis (adjustment for age, sex, race, body mass index, smoking, physical activity, occupation, energy intake, protein intake, and fat intake), respectively.
Conclusion
Higher dietary intakes of caffeine were associated with 25(OH)D deficiency in a representative sample of the American population. Further studies are crucial to determine causation.
