What is Vitamin D Deficiency?
What is Vitamin D deficiency?
Ideal levels of vitamin D, 25-hydroxy: 30-50ng/mL (75-125 nmol/L).
Subclinical vitamin D deficiency is present when there are lower than normal Vitamin D levels in the blood. (“subclinical” is when a disease is not significant enough to cause visible symptoms).
Why is Vitamin D important?
Vitamin D helps maintain calcium levels, metabolism, cellular activities, boosts immunity, and is crucial for bone health and strength.
Why am I low in Vitamin D?
Low vitamin D diet
- Not many foods contain high levels of Vitamin D and even then, Vitamin D must be converted to an active form by the liver and kidneys.
- Vitamin D rich foods: eggs, milk, salmon, cheese, tuna, sardines, cod liver oil, orange juice, and kale.
Reduced vitamin D absorption by the body is typically due to malabsorption conditions like inflammatory bowel disease or celiac disease
Reduced sun exposure or increased sunscreen use
- The majority of vitamin D is synthesized in the skin when exposed to sunlight.
Increased liver breakdown of vitamin D
What are possible symptoms?
- People with mild to moderate deficiencies (levels between 15-20ng/mL) will not likely experience symptoms.
- People with severe deficiencies (levels < 10ng/mL) may develop osteomalacia (bone softening).
What are risk factors for low vitamin D?
- Low sun exposure
- Dark skin
- Certain medications reduce vitamin D (ie: phenytoin)
- Inflammatory bowel disease
- Celiac disease
Prolonged and severe vitamin D deficiency can result in abnormal calcium and phosphorus levels; these imbalances can cause hyperparathyroidism and osteomalacia.
What are possible treatments?
People with Vitamin D levels 10-20ng/mL do not normally need any additional evaluation and may supplement with an over-the-counter vitamin D3.
- Ages 1 to 70 years old should have 600-800 IU of Vitamin D3 per day.
- People older than 70 years should have 800 IU of Vitamin D3 per day.
People with malabsorption issues (celiac or inflammatory bowel disease) may require higher doses overseen by their medical provider.
People with levels < 10ng/mL are at risk for osteomalcia and should have additional blood work and assessment by a medical provider.
Where can I get more information?
For additional information, please seek further guidance from your primary care provider.
Dawson-Hughes, B. (2017). Vitamin D deficiency in adults: Definition, clinical manifestations, and treatment. In M. K. Drezner & C. J. Rosen (Eds.), UptoDate. Available from: https://www.uptodate.com/contents/vitamin-d-deficiency-in-adults-definition-clinical-manifestations-and-treatment
Rosen, H.N. (2018). Calcium and vitamin D supplementation in osteoporosis. In C.J., Rosen & K.E., Schmader (Eds.), UptoDate. Available from: https://www.uptodate.com/contents/calcium-and-vitamin-d-supplementation-in-osteoporosis