Research
Micronutrients & recovery
Higher BMI and body fat percentage significantly reduce the efficacy of vitamin D supplementation, resulting in smaller increases in circulating 25(OH)D concentrations compared to leaner individuals.
If you have a higher BMI, standard vitamin D doses may be less effective because the vitamin gets stored in fat tissue rather than circulating in your blood. You may need higher doses to achieve the same blood levels as a leaner person. This is a known physiological effect, not a lack of effort.
GoodQualifiesHIGH confidence
Higher body fat percentage or higher BMI have been associated with smaller increases in 25(OH)D concentrations in response to vitamin D supplementation... The adjusted change was 20% less in those with ≥30 compared to those in the <25 kg/m² category.
Why this rating
Consistent findings across multiple studies, though some small studies failed to show significance due to narrow BMI ranges.
Source
Factors Affecting 25-Hydroxyvitamin D Concentration in Response to Vitamin D Supplementation
Hajar Mazahery et al. · Nutrients · 2015
narrative_reviewCited 209×
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