Here comes the sun: All about Vitamin D
by Daniel Okubo, MD
On our quest to maximize health and maintain our youth, many of us have wondered, “Do I need more vitamin D?” For most reading this, the short answer is “probably,” remembering that balance and moderation is the key.
Vitamin D is most associated with maintaining calcium levels and bone density. Vitamin D helps to absorb calcium from the food we eat (yes, adequate calcium is one more thing we need to think about!), making calcium available for our bones. Too little vitamin D can result in the weakening of bones and possibly bone fractures.
Our skin naturally produces vitamin D when exposed to ultraviolet B (UVB) waves in sunlight. It is also naturally found in foods like fish, cheese, milk, and eggs, and can be a supplement in breakfast cereals. Those at higher risk for low levels of vitamin D include individuals who are dark-skinned, obese, have intestinal disease or had gastric bypass surgery, are living in nursing homes, or those with limited sun exposure. For those of us living in Minnesota, where we often have to cover every square inch of skin, we usually rely on the vitamin D we get in foods.
We advise that breastfed infants and older adults receive vitamin D supplements, but recommendations are less clear for other age groups. The United States Preventative Services Task Force (USPSTF) has not found sufficient evidence to recommend vitamin D supplements for all adults. When reading these recommendations, it is important to remember that these organizations consider all Americans, and must make recommendations applicable to those living in areas that can be as different as Minnesota and Hawai’i. Because vitamin D levels are based on sun exposure and diet, the decision to take supplements must be individualized.
Closer to home, the Minnesota Department of Health recommends children and adults consume 600IU of vitamin D daily from all sources. Most people have a hard time determining how much vitamin D they get from foods and from the sun each day. The National Institutes of Health estimates that the average vitamin D intake for males from foods alone ranges from 204 to 288 IU a day, and from 144 to 276 IU a day for females; numbers that are less than half of the Department of Health’s recommendation. If you live in Minnesota and your diet does not heavily consist of fish, milk, and eggs, you are likely not getting enough vitamin D. However, this does not mean you need to rush to get your vitamin D level checked, as testing can be expensive and largely unhelpful if you are not in a high risk group.
If you are concerned that you do not get enough vitamin D, first be sure to eat a balanced diet that incorporates foods naturally containing vitamin D. Go for regular walks or play outside with as much of your skin exposed as is safe, both in summer and in winter. If your goal is to lower your risk of bone fractures, also be sure to make time to exercise regularly, as the USPSTF strongly recommends the importance of exercise programs to prevent falls and injuries.
Once you have successfully incorporated these changes into your normal routine and, if you can afford to spare roughly $10 a month, you should consider taking a vitamin D supplement just to be safe. It is recommended that you take 400IU of supplemental vitamin D as part of a multivitamin, or separately in tablets or liquid droplets with vitamin D3 (cholecalciferol) being the preferred form over vitamin D2 (ergocalciferol). One helpful tip for pill-adverse children (and adults) is that liquid vitamin D drops can be mixed into most foods.
Again, balance and moderation are essential. There is no clear benefit to taking more than the recommended amount of vitamin D each day. Too much vitamin D can result in heart problems or raise blood levels of calcium, which could eventually damage the heart, blood vessels, and kidneys. If you have any questions, I would encourage you to find time to have a discussion with your doctor about your individualized risk for low levels of vitamin D, and how to best live your happiest and healthiest life.
