To D or Not to D: Vitamin D Basics
Some people tout vitamin D as a silver bullet for everything from osteoporosis and bone health to depression and the common cold. Most experts do agree that this powerful vitamin is no ordinary nutrient. In fact, it acts more like a hormone than a vitamin; your body even makes vitamin D just like it produces hormones. And just like a hormone, it is critical for several important functions.
“For years, scientists have known that vitamin D enhances the absorption of calcium, which helps protect bones and prevent fractures and falls,” explains Amardeep Mann, M.D., an internal medicine doctor at Henry Ford Health System. “However emerging research, though exciting, does not prove a role for vitamin D supplementation in warding off chronic diseases, including cancer and autoimmune diseases.”
Unfortunately, most Americans don’t get enough vitamin D to maintain good bone health, never mind protect against fractures and falls. According to some estimates, nearly 70 percent of Americans have blood levels that are deficient in vitamin D, and up to 15 percent are severely D deficient.
While research hasn’t shown that supplementing with vitamin D can protect against disease beyond osteoporosis, it still makes sound scientific sense to maintain adequate levels of this important nutrient. Here’s how:
- Don’t shun the sun. “The body can make 200 International Units (IU) of vitamin D in just 15-30 minutes of unprotected exposure to sunshine,” Mann says. “The recommended daily dose is 600 IU for adults.” While no one is suggesting it’s a good idea to bathe in the sun (due to the risks of too much sun exposure), taking a 10-15 minute stroll without sun protection packs a hefty dose of vitamin D and can instantly lift your mood as well.One thing to note: People with light skin tones are more efficient than those with darker skin at synthesizing the vitamin from the sun. So if you’re fair-skinned, you’ll make your dose of D faster.
- Choose vitamin D-rich foods. Fatty fish and most types of mushrooms are the best natural food sources of vitamin D, but you can also find this vitamin in a mix of fortified foods. Milk, yogurt, orange juice and cereal all tend to have extra vitamin D added.
- Take a supplement. It can be tough to get adequate vitamin D from food alone. “Unless you’re drinking a liter of vitamin D-fortified milk a day — which could cause other concerns — it makes sense to take a supplement,” Mann says. Choose vitamin D3 over D2 since it’s more active form of vitamin D. Aim for 600 IU daily if you’re under 70 and 800 IU if you’re over 70, since your ability to synthesize vitamin D from the sun decreases with age.
Worried you’re running low on D? Talk with your doctor. Based on your consultation and any test results, you and your physician can decide if you need a supplement and how much vitamin D you need to take daily.
“People who are taking steroids, or who have a chronic disease such as kidney disease, Crohn’s disease or another digestive disorder may require additional supplementation,” says Dr. Mann. “For the rest of the population, taking 600 IU daily should suffice.”
While some vitamin D is good, more is not necessarily better. Too much vitamin D may cause nausea, vomiting, poor appetite, constipation, weakness and weight loss. More seriously, it can also raise blood levels of calcium, resulting in confusion and heart rhythm abnormalities.
To find a doctor or allergist at Henry Ford, visit henryford.com or call 1-800-HENRYFORD (436-7936).
Dr. Amardeep Mann is an internal medicine physician seeing patients at Henry Ford Medical Center – Farmington Road in West Bloomfield.