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Vitamin D deficiency: a worldwide problem with health consequences
1Department of Medicine, Boston University School of Medicine, 715 Albany Street, M-1013, Boston, MA 02118, USA. mfholick@bu.edu
The American Journal of Clinical Nutrition
|April 11, 2008
Summary
Vitamin D deficiency is a global pandemic, often caused by insufficient sun exposure. Supplementation with 800-1000 IU of vitamin D3 daily may be necessary to maintain optimal health levels.
Area of Science:
- Endocrinology
- Nutritional Science
- Public Health
Background:
- Vitamin D deficiency is a widespread pandemic.
- Limited natural food sources and inadequate fortification contribute to deficiency.
- Sun exposure is the primary natural source of vitamin D.
Purpose of the Study:
- To highlight the prevalence and causes of vitamin D deficiency.
- To outline the health consequences of vitamin D deficiency.
- To recommend adequate vitamin D intake for optimal health.
Main Methods:
- Review of current scientific literature on vitamin D.
- Analysis of the role of sun exposure and dietary intake.
- Examination of health outcomes associated with vitamin D levels.
Main Results:
- Vitamin D deficiency is linked to rickets, osteopenia, osteoporosis, and fractures.
- Deficiency is associated with increased risks of cancers, autoimmune diseases, hypertension, and infections.
- A serum 25-hydroxyvitamin D level above 75 nmol/L (30 ng/mL) is needed for optimal health benefits.
Conclusions:
- Moderate sun exposure is crucial for maintaining adequate vitamin D levels.
- Supplementation of 800-1000 IU of vitamin D3 daily may be required without sufficient sun exposure.
- Vitamin D2 can be effective in maintaining 25-hydroxyvitamin D concentrations.
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