A: Here’s the basic scoop on vitamin D (and D-2 and D-3 supplements): D-3 is formed in the body as a result of the skin’s exposure to sunlight and is found in some fish, like salmon and trout. Vitamin D-2 is a fungus/yeast-derived product, and is available only through supplementation and is added to foods. Both D-2 and D-3 precursors are hydroxylated in the liver and kidney, and both create an inactive storage form of the vitamin and a bioactive form.
If you do not produce enough of the bioactive and storage forms of D (35 percent or more of indoor-dwelling, sun-protected folks are deficient), some studies indicate that you are at increased risk for infections, some cancers, brittle bones, cardiovascular woes and intestinal troubles.
So what should you do? We think everyone should supplement 1,000 IU a day — and have blood levels checked to see if they need more. But which: D-2 or D-3? Well, there’s evidence that in the body it may all come to the same thing, as long as you don’t overdo D-2. A 2013 study out of Boston University found that vitamin D-2 is as effective as vitamin D-3 in maintaining circulating concentrations of 25-hydroxyvitamin D (also called 25-OH vitamin D, it’s the bioactive form) and taking D-2 didn’t negatively affect circulating D-3 levels. And another study in older folks also found both D-2 and D-3 raised their circulating levels equally.
So check with your doc to see if you need more than 1,000 IU supplement daily and don’t fret too much about choosing D-2 or D-3. Also, try to get 10 minutes of sunlight a day without sunscreen, and eat plenty of oily fish (3.5 ounces of salmon has around 360 IU of D).
Q: I heard about a study that said the Brits actually had better teeth than Americans! Is it because they have a public health care system that covers dental? — James F., Brooklyn
A: You’re referring to the study recently published in the British Medical Journal that said U.S. citizens averaged more missing teeth (7.31) than the Brits (6.97) — a difference of about a third of a tooth. All things considered, in the end the study found that, contrary to popular myth, the Brits just don’t have worse teeth than Americans.
That study comes on the heels of the World Health Organization’s global ranking of health care: They rank the British health care system 18th in the world; the U.S. is 37th! (FYI: Canada is ranked 30th.) However, dental coverage is not part of the reason why the British health care system is higher-rated than U.S. health care, as it also fails to provide basic dental care for most people. (We could improve our global health care ranking if we provided dental care and did it efficiently! Our system is ranked 37th in part because we spend more and get considerably less; in other words, we’re less efficient with our health care dollars than 36 other countries.)
All health care systems would be smart to cover dental care, because good dental health can prevent many other illnesses. For instance, periodontal (gum) disease is linked to heart attack, stroke, lung disease, diabetes and even complications of low birth weight in infants. Recently, it’s been linked to breast cancer too. So much of your health depends on your dental hygiene because your mouth is your immune system’s frontline defense. Once that’s compromised …
So right now, do whatever you can to keep your teeth and gums healthy (brush twice and floss once daily). And if you need dental work but are financially stretched, here’s a tip: Dental schools offer reduced fees if you’re willing to be cared for by a (well-supervised) future dentist. You can find an affordable dentist near you at www.HHS.gov; search for low-cost dental care.
Dr. Mehmet Oz is host of “The Dr. Oz Show,” and Dr. Mike Roizen is Chief Wellness Officer and Chair of Wellness Institute at Cleveland Clinic. Email your health and wellness questions to firstname.lastname@example.org.