There’s been a lot of chatter about vitamin D lately so I’d like to synthesize the information and give you a comprehensive overview of this essential supplement. Vitamin D is a fat-soluble vitamin not naturally found in many foods, hence the fortifying of foods such dairy products, orange juice and some cereals. Our bodies can produce it through the sun’s ultraviolet rays hitting our skin.
Vitamin D regulates our neuromuscular and immune function and reduces inflammation.
Studies show that people with higher levels of vitamin D have a lower risk of breast cancer, colon cancer, prostate cancer, heart disease, depression, weight gain, and other maladies, though they do not definitively prove that lack of vitamin D causes disease.
“Vitamin D and skin cancer risk has been a really hot topic lately,” said Dr. Asgari. “There’s a whole lot of new evidence showing our vitamin D levels are probably insufficient, and vitamin D insufficiency may be linked with certain cancer risk. But the overall take-home message of our study is that vitamin D is not associated with decreased melanoma risk.” Maryam Asgari, M.D., from Kaiser Permanente in Oakland, Calif., Society for Investigative Dermatology Montreal, May 2009.
Data shows that we don’t get enough vitamin D and without sufficient levels our bones can become thin, brittle, or even distorted (rickets in children and osteomalacia in adults). It is essential for bone growth and bone remodeling as it promotes calcium absorption in the gut.
Mother Knew Best
I sometimes have a dilemma when I meet a patient who blood tests show Vitamin D deficiency. I know if I advise them to go out in the sun daily with no protection against UV rays they’ll get adequate amounts of Vitamin D, but run the risk of melanoma skin cancer. Maybe Mom’s were right when she asked us to go play outside. But those days have long been gone since parents are now concerned with safety and smog. Also sunscreen on children should be a first line of defense with children playing outdoors regardless if they synthesize less Vitamin D.
The Healthy Answer Solution
So what is the solution to getting adequate vitamin D daily if you can’t get it from the best and natural source – the sun?
Diet can help. Our mother’s also knew something when begged us to take cod liver oil and fed us beef or calf liver (both excellent sources of vitamin D), but as we got older, we exerted our rights and gave up on these unwanted delicacies! Other sources are oily fish, like salmon and mackerel, tuna and sardines packed in oil, milk, cheese, and egg yolks. But eating these foods in quantities sufficient to provide adequate vitamin D can cause weight gain. And the high fat content doesn’t make for a heart-healthy diet.
Supplements provide a good source of vitamin D. The current recommended daily dose is 200 IU for ages up to 50; 400 IU for those of us between 51 and 70; and 600 IU for the over 70 group. However, Boston University vitamin D expert Michael Holick, MD PhD, says this isn’t enough. He recommends a dose of 1,000 IU a day of vitamin D for both infants and adults – unless they are getting plenty of safe sun exposure.
Mixing vitamin D with calcium solves two possible deficiencies and they, along with vitamin K, complement each other promoting maximum absorption.
Discuss your vitamin D needs with your doctor. A simple blood test – the 25(OH)D or calcidiol test – will show if your levels are low. With these tests your doctor will also be aware of any medications you are taking that might affect negatively vitamin D absorption.
My advice is to get a little sun, lots of fresh air and exercise, eat a healthy diet and take a good daily supplement.