Vitamin D: Wonder Pill or Overkill?
Wouldn’t it be great if one vitamin could build stronger bones and protect against diabetes, multiple sclerosis, cancer, heart disease, and depression? Or even help you lose weight? Researchers have high hopes for vitamin D — which comes from our skin’s reaction to sunlight, a few foods, and supplements. Learn the facts, and see who’s at risk for a “D” deficiency.
Vitamin D Boosts Bone Health
Vitamin D is critical for strong bones, from infancy into old age. It helps the body absorb calcium from food. In older adults, a daily dose of “D” and calcium helps to prevent fractures and brittle bones. Children need “D” to build strong bones and prevent rickets, a cause of bowed legs, knock knees, and weak bones. Adding the vitamin to milk in the 1930s helped to nearly eliminate the disorder.
Vitamin D and Multiple Sclerosis
Multiple sclerosis (MS) is more common far away from the sunny equator. For years, experts suspected a link between sunlight, vitamin D levels, and this autoimmune disorder that damages the nerves. One newer clue comes from a study of a rare gene defect that leads to low levels of vitamin D – and a higher risk of MS. Despite these links, there’s not enough evidence to recommend vitamin D for the prevention or treatment of MS.
Vitamin D and Diabetes
Some studies have shown a link between a low vitamin D level and type 2 diabetes — the more common version of this blood sugar disorder. So, can boosting your vitamin D levels help ward off the disease? There’s not enough proof for doctors to recommend taking this supplement to prevent type 2 diabetes. Excess body fat may play a role in diabetes and low levels of vitamin D.
Vitamin D and Weight Loss
Studies have shown that people who are obese often have low blood levels of vitamin D. Body fat traps vitamin D, making it less available to the body. It’s not clear whether obesity itself causes a low vitamin D level or if it’s the other way around. But one small study of dieters suggests that adding vitamin D to a calorie-restricted diet may help overweight people with low vitamin D levels lose weight more easily.
How Does Sun Give You Vitamin D?
Most people get some vitamin D from sunlight. When the sun shines on your bare skin, your body makes its own vitamin D. But you probably need more than that. Fair-skinned people might get enough in 5-10 minutes on a sunny day, a few times a week. But cloudy days, the low light of winter, and the use of sun block (important to avoid skin cancer and skin aging) all interfere. Older people and those with darker skin tones don’t make as much from sun exposure. Experts say it’s better to rely on food and supplements.
Dining With Vitamin D
Many of the foods we eat have no naturally occurring vitamin D. Fish such as salmon, swordfish, or mackerel is one big exception — and can provide a healthy amount of vitamin D in one serving. Other fatty fish such as tuna and sardines have some “D,” but in much lower amounts. Small amounts are found in egg yolk, beef liver, and fortified foods like cereal and milk. Cheese and ice cream do not usually have added vitamin D.
Vitamin D Supplements
Eating D-rich foods is the best way to get vitamin D. If you still need help getting enough, there are two kinds of supplements: D2 (ergocalciferol), which is the type found in food, and D3 (cholecalciferol), which is the type made from sunlight. They’re produced differently, but both can raise vitamin D levels in your blood. Rodan + Fields Essentials Maximum D3, is an oral supplement. Each capsule, taken weekly, contains 10,000 IU of the most absorbable form of Vitamin D. Check with your health care provider for the best supplements for your needs.
Are You Vitamin D Deficient?
Problems converting vitamin D from food or sunshine can set you up for a deficiency. Factors that increase your risk include:
- Age 50 or older
- Dark skin
- A northern home
- Overweight, obese, gastric bypass surgery
- Milk allergy or lactose intolerance
- Liver or digestive diseases, such as Crohn’s disease or celiac
How Much Is Too Much Vitamin D?
Some researchers suggest taking far more vitamin D than the 600 IU daily guideline for healthy adults. But too much be dangerous. Very high doses of vitamin D can raise your blood calcium level, causing damage to blood vessels, heart, and kidneys. The Institute of Medicine sets the upper tolerable limit at 4,000 IU of vitamin D per day. You can’t get too much vitamin D from the sun. Your body simply stops making more. But sun exposure without sunscreen can raise your risk of skin cancer.