Earlier this year, I had my vitamin D level checked for the first time in my life. I was just curious to see if I had adequate levels, since osteoporosis runs in my family. A recent study (OC13) by New Delhi researchers showed that over 75% of hip fracture patients had low vitamin D levels.
No way this could be me. Smiling with confidence, I just knew my level would be sky high. I popped my vitamins and calcium every day and am outdoors all of the time. Well, you can imagine my shock when my level returned quite low. Staring in disbelief at the lab report, I thought to myself, “How could this be?” followed by, “If I have a problem, I’ll bet lots of other folks do, too.”
I was placed on high dose vitamin D supplements and follow up reports showed that I had more than restored my levels. While popping my D, I made sure my patients had their levels checked. Lo and behold, almost half of them also had lower than normal levels requiring additional supplementation.
Many of my colleagues and I began to believe that the current RDA of vitamin D (200IU) which was set in 1997 may be too low to accommodate our current lifestyles. No sooner did we all utter those words than a new Institute of Medicine (IOM) report was issued increasing the RDA to 600 IU, and 800 IU for people over 70 years of age. Frankly, many doctors and scientists felt that the recommendation is still too low. Here’s some back story to help guide your own thinking about how this may affect your health.
Vitamin D is one of the fat soluble vitamins (e.g. A, D, E, K). Make sure to eat some fat containing food (e.g. nuts, low fat dairy) for optimal absorption. There are two main forms of the vitamin: D2 (ergocalciferol) and D3 (cholecalciferol). Catching ultraviolet B rays will increase your D3 levels. Fatty fish, mushrooms, eggs and meat are rich in D, as well as foods specifically fortified with D. Vitamin D is essential for the proper absorption of calcium and phosphate. That’s why vitamin D is so critical for bone health.
What you may not know is that recent research has also shown that adequate vitamin D levels are necessary for optimal immune, cognitive and neuromuscular function, the reduction of inflammation, and control of genes that can influence our tendency toward certain diseases, including diabetes, heart disease and cancer. The IOM report acknowledged this new research but the IOM panel members didn’t feel the data was strong enough to increase the RDA further. So, the levels they have recommended apply to bone health only, where the cause and effect data is stronger.
How does someone become vitamin D deficient? Remember the age old recommendation to get your 15 minutes of daily sunshine? Well, as it turns out, that may not be enough. A study of young Hawaiian skateboarders and surfers found that over 50% of them had vitamin D levels lower than average. Slathering on sunscreen could be an issue in blocking adequate absorption. What was really interesting was that the vitamin D levels of these tropical sun bathing folks were compared to levels among Wisconsin residents who were taking vitamin D supplements and who aren’t riding waves or boogying down the sidewalk on their boards. Guess who had better levels? Yep, it was the pale skinned Midwesterners. Apparently outdoor training and recreation wasn’t cutting it for maintaining adequate vitamin D levels. And my sunscreen ritual was a good news, bad news story. While blocking sun rays, I block absorption of enough sunlight to bump up my vitamin D levels.
What about natural food sources?
- Fatty Fish: catfish, salmon, mackerel, sardines, tuna and eel. It looks like salmon is all I’m getting from this source.
- Eggs: my weekly omelet is apparently not cutting it
- Beef liver: nope, not a fave of mine
- Cod liver oil: not happening
- Mushrooms: love these, but would have to eat a mountain of them
There are also fortified sources of D including milk, orange juice and cereals. I don’t consume enough of either to make a substantial difference.
What should your vitamin D level be? Here’s the rub. The IOM panel recommends 20 ng/ml as a sufficient level, while some vitamin D advocates, including the Endocrine Society and the International Osteoporosis Foundation, note that 30 ng/ml is necessary for optimal bone health. Can you have too much? Experts agree that levels above 50 ng/ml may pose an increased cancer risk. But, that’s not the problem for most of the population. Not having enough D on board is the critical issue.
The good news is that emerging information about vitamin D’s potential for disease prevention has prompted excellent new research studies. For instance, the National Institutes of Health has initiated a study to include 20,000 men and women over 60 years of age to study whether 2,000 IU of vitamin D, omega-3 fatty acids from fish oil, or placebo will lower the risk of heart disease. Stay tuned!
Meanwhile, what should you do?
- Get your vitamin D level checked. This is especially important for those people who are getting little sun, are at risk for osteoporosis, may have inadequate dietary intake and are either taking no vitamin supplements or are taking them sporadically. It’s just good to get a baseline. Knowledge is power.
- Discuss your vitamin D status and supplements with your medical team. Because there is controversy surrounding the IOM report regarding what is a normal D level and supplement intake, you need to talk with your medical professional about your individual situation. Your gender, age status, level of physical activity, nutrition intake, bone status, osteoporosis risk, and sun exposure are all factors that must be considered. Then add to this your D level and you can have a comprehensive discussion about next steps to optimize your D status.
- Add up your daily D. Just for grins, whip out your supplements and add up how much D you’re actually consuming. Multivitamins contain D at varying levels, while calcium supplements are usually fortified with D. Check out how much D you’re consuming from foods sources including fortified dairy and cereals. This will help you monitor your total intake. And, it will be helpful to share this information with your medical team when you’re deciding how much D you need on a daily basis.
- Soak up a few rays. Even though we now know that 15 minutes in the sun is probably not enough to bump your D levels sky high, it’s still good to get outdoors to reap whatever benefit you can from the sun, as well as enjoy your external environment while staying physically active. Just remember to smooth on that sunscreen after 15 minutes of exposure or you’ll never hear the end of it from your dermatologist.
- Eat D-licious foods. You saw the laundry list of natural food sources for vitamin D. If you eat salmon, try to get the wild (not farmed) type, as it has fewer contaminants. I’m increasing my egg consumption and integrating more mushrooms into my daily salads and side dishes.
The OC13 study was presented at the IOF Regionals — 1st Asia-Pacific Regional Osteoporosis Meeting being held in Singapore from December 10-13, 2010. Abstract published in Osteoporosis International, Vol. 21, Suppl. 5, 2010
Binkley, N; Novotny, R; Krueger, D; Kawahara, T; Daida, YG; Lensmeyer, G; Hollis, BW; Drezner, MK (2007). “Low vitamin D status despite abundant sun exposure”. The Journal of Clinical Endocrinology and Metabolism 92 (6): 2130–5.
Hollis, B; Wagner, C; Drezner, M; Binkley, N (2007). “Circulating vitamin D3 and 25-hydroxyvitamin D in humans: An important tool to define adequate nutritional vitamin D status”. The Journal of Steroid Biochemistry and Molecular Biology 103 (3–5): 631–4.