What Causes Vitamin D Deficiency
6 Common Causes of Vitamin D Deficiency
The best source of vitamin D is having daily exposure to sunlight. This is easy if you live in a warm sunny climate and spend 15-30 minutes a day outdoors with bare arms and legs. However, those who live in colder climates with long dark winters are highly likely to need vitamin D supplements.
Pollution can block the sun’s rays very effectively. If you live in a city, being outdoors may not necessarily be giving you the vitamin D you need.
Although we hear a great deal about the danger of skin exposure to the sun, being constantly covered head to toe in sun block limits the body’s ability to absorb the sun’s rays and generate vitamin D. Spend the first 15 minutes outdoors each day without sunscreen to benefit from this important natural source of vitamin D.
Aging skin does not absorb sunlight as well as younger skin, so older people may lack vitamin D. They are also less likely to take part in outdoor sports or may have medical conditions that limit their opportunity to spend time outdoors. Certain medicines such as steroids and anti-seizure drugs also inhibit the absorption of vitamin D. Finally, kidneys in older people are less able to convert vitamin D to its active form and therefore cause a vitamin D deficiency.
The increased melanin pigment in darker skin reduces the skin’s ability to make vitamin D from sunlight. Studies show that older adults with darker skin are at particularly high risk of vitamin D deficiency.
Those who are clinically obese, with a body mass index (BMI) of over 30, frequently have low levels of vitamin D. Vitamin D in the blood is extracted by the fat cells, which alters its availability for release in the body.
The only way to know if you are receiving sufficient vitamin D on a daily basis from your diet and sunshine is by an expensive 25-hydroxy blood test which is not routinely performed. Unfortunately, you are unlikely to know if you are vitamin D deficient until it is too late and you have brittle bones, frequent fractures or osteoporosis. To be on the safe side, take a supplement of vitamin D daily. Current recommended requirements of vitamin D are 800-1000 IU, but most informed sources feel this is woefully inadequate and recommend double that amount.