Vitamin D Guide
Your comprehensive guide to vitamin D - the sunshine vitamin essential for bone health, immune function, and overall wellness.
Understanding Vitamin D
Why vitamin D matters for your health
Vitamin D is a crucial nutrient that your body can produce from sunlight exposure or obtain through diet and supplements. It plays essential roles in calcium absorption, immune function, and maintaining healthy bones.
Natural Production
Your skin produces vitamin D when exposed to UVB rays from sunlight
Immune Support
Supports immune system function and helps regulate inflammation
Bone Health
Essential for calcium absorption and maintaining strong bones
Sun Exposure vs. Supplementation
Comparing natural and supplemental sources of vitamin D
Sun Exposure Benefits
- Natural production through UVB rays
- Free and easily accessible
- Produces both D2 and D3 forms
- Regulated by your body's needs
Supplementation Benefits
- Reliable year-round availability
- Precise dosing: Exact amounts for optimal levels
- No weather dependence: Works regardless of season or location
Limitations of Sun Exposure
- • Location and season
- • Skin pigmentation
- • Sunscreen use
- • Indoor lifestyles
- • Age
Deficiency Risk Factors
Who is at higher risk?
Lifestyle Factors
- Limited sun exposure: Indoor lifestyles
- Dark skin pigmentation: Melanin reduces production
- Age: Older adults need more
Medical Factors
- Obesity: Vitamin D stored in fat
- Malabsorption: Celiac disease
- Medications: Steroids
Common Symptoms
Vitamin D deficiency symptoms
- • Fatigue
- • Bone pain
- • Infections
- • Depression
- • Wound healing
Testing
Determine vitamin D status
Blood test for 25-hydroxyvitamin D
Deficient
< 20 ng/mL
((50 nmol/L))
Insufficient
20-29 ng/mL
((50-74 nmol/L))
Sufficient
≥ 30 ng/mL
((75 nmol/L))
When to Test
- At-risk individuals
- Winter months
- Symptoms present
- Before supplementation
- After supplementation
References
Based on NIH info
Visit NIHhttps://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
Key studies cited
See Also: Fat-Soluble Vitamins
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