D is for Deficiency - Vitamin D
The word is out. Recent studies confirm that well over half the U.S. population is deficient in vitamin D. Chances are that you are at risk, particularly if you have food allergies or celiac disease.
Vitamin D is produced naturally through sunlight synthesis on our skin. In times past, people got much of this important nutrient through sun exposure. But the reality of modern-day living is that most of us spend much of our time indoors and when we do venture out, we slather on the sunscreen. Sun protection is good practice but SPF 15 sun lotion inhibits 99 percent of D synthesis. Most of us just won’t get adequate vitamin D from the sun. In one study of healthy Hawaiians with sun exposure of over 25 hours per week, 51 percent demonstrated insufficient blood levels of vitamin D.
It’s also unlikely we can obtain enough Vitamin D from diet. The best food sources, such as salmon and sardines, have come under suspicion (risk of toxicity from mercury or PCB). Some commercial cereals and milk are D fortified, but it may take drinking 20 to 40 glasses of milk per day to replete a deficiency. All this, plus the fact that our intestinal lining must be healthy in order to properly absorb this fat-soluble nutrient, it’s no surprise that some of the most severe cases of D deficiency are found among food-allergic and celiac patients.
In the short-term, vitamin D deficiency only occasionally manifests with symptoms, such as bone pain, bone fracture (from minor injury), loose teeth, poor balance, weak hip muscles. But the long-term impact on overall health is profound —and potentially devastating.
Many people know that severe deficiency can cause rickets in children and osteomalacia (a bone disease) in adults. Yet more moderate deficiency is associated with infertility, autism, cardiovascular disease, high blood pressure, heart attack, osteopenia, osteoporosis and at least 19 forms of cancer. Studies also link insufficient D to schizophrenia, irritable bowel syndrome, fibromyalgia and certain types of chronic pain. In addition, D deficiency leads to an imbalanced immune system. For some people, this results in allergy, eczema and asthma. For others, it leads to autoimmune conditions, such as type 1 diabetes, rheumatoid arthritis, multiple sclerosis or Parkinson’s disease.
How do you know if you’re getting enough D? A simple, inexpensive blood test is available from your doctor. Ask for a serum 25-OH vitamin D level. Normal levels range from 32 to 100 ng/m. Most healthcare professionals won’t intervene if your level is above 32. However, mounting evidence suggests that, for optimal health, levels should be between 50 and 70 ng/m. Most people can’t achieve this level without supplementation under physician supervision. A good start is taking 1000 to 3000 IUs of cholecalciferol (vitamin D3) daily.
Vitamin D is available in tablets, capsules and drops at most health food stores and pharmacies. Higher-dose capsules (4000 IU to 5000 IU) are often available from physicians and chiropractors that specialize in wellness and nutrition. With physician supervision, high dose oral supplementation with 50,000 to 100,000 IUs or up to 400,000 IU injectable vitamin D can be safely prescribed.*
The wonders of vitamin D are still under investigation. Promising research has shown that maternal supplementation with vitamin D reduces infant asthma and wheezing rates and that babies supplemented with vitamin D have a lower rate of developing adult-onset diabetes. One compelling study found that post-menopausal women supplementing with calcium and vitamin D over four years contracted 77 percent fewer cancers. The cancer prevention mechanism may be related to a stronger, healthier immune system. Numerous clinical trials are currently investigating this link.
Correcting D deficiency costs only pennies a day—and the potential health benefits are enormous. There may be no medical intervention available today that is as cost effective or as wide reaching as adequate vitamin D supplementation.
Ellie W. Campbell, DO, is a family doctor with Campbell Family Medicine in Atlanta, Georgia.
J.T. Hunt assisted with this article. LW
*Daily doses above 3000 IU should be taken under doctor supervision. Vitamin D overdose is extremely rare, usually related to accidental overdose of prescription-strength Vitamin D or manufacturer labeling error. Symptoms include loss of appetite, nausea, itching, excessive thirst and urination and potential kidney failure.