This week I traveled to Boston for my yearly American Dietetic Conference.  While St. Louis was warm and unseasonably sunny, the weather in Boston was cold and dreary.  I definitely did not get my dose of a very important hormone/vitamin called “D.”  Of all conference sessions I attended, researcher Dr. Holick’s presentation on “delightful D” was one of the most interesting.  Leaving his conference room, instead of heading to the next session, I wanted run to the closest GNC and  pick up a container of these “miracle pills.” While I was previously aware of the benefits of vitamin D on bone health, I had NO idea of the impact this vitamin had on other common diseases, and the prevalence of deficiencies in the US – more than 50% of us are likely to have low levels. So, what if I’m deficient? What are the risks? The list of potential implications is a long one.  Low vitamin D status is associated with increased risks of common cancers such as breast and prostate, diabetes, osteoporosis, depression, the flu, heart disease, rheumatoid arthritis, high blood pressure and the list goes on…In fact, if you want to read about the others check out a summary of the research . It is hard to imagine that one vitamin could be so important. Vitamin D, called a vitamin, actually acts more like a hormone, and thousands of our cells and tissues contain receptors for vitamin D.  So put very simply, if you are low on vitamin  D, and these receptors are not filled, the cells and tissues do not function to their optimal potential and things go wrong, aka disease. So how can I get more vitamin D?  The majority of vitamin D is made in our skin when it is exposed to sunlight. We can also get vitamin D from foods such as fatty fish and dairy, but the amounts in these foods are small, for example you would have to eat 4 oz of salmon 5-7 days a week to get the recommended amounts of “D”  Dr. Holick and others recommend we need. To get adequate vitamin D from the sun, your body requires 15-20 minutes of sunlight to the arms and legs 3-5x  week. Important to know, SPH30 prevents 99% of your skin’s ability to make vitamin D, and you can only make adequate D between the hours of 10am-3pm.  Individuals who live above the latitude line of Atlanta will rarely make enough during the winter, and if you are dark skinned, you are unable to make as much vitamin D as a lighter skinned individual. So, now…you can see the challenge of getting enough of this hormone.  We wear sunscreen, we are inside working between the hours of 10am and 3pm, and we don’t live sunny climate year round. How do you know if you are deficient? Ask your doctor to check your vitamin D status, and it can be completed though a simple blood draw.  This assay has quickly become the #1 test requested by patients and ordered by physicians.  Your savvy doc might already be on top of it!Sounds like I might need a supplement, so how much should I take? The most current literature suggested by studies says: 0-1 years of age: 400-1000 IU/day 1-12 years of age: 1000-2000 IU/day 13+ years of age: 1500-2000 IU/day Those who are overweight/obese: 2-3 times more. Vitamin D2 or D3 are acceptable forms to take, and D3 can be purchased over the counter, and D2 is typically prescribed by your physician. The current Dietary Reference Intake is 400 IU/day, and I can easily forecast that this DRI will be increasing to address the wealth of  research on this important hormone. I have, and always will remain to advocate getting your nutrition through food first, and relying on supplements only when shown to be necessary. However, with vitamin D, my opinion is  different. If a simple vitamin D supplement can reduce your risk of cancer,  boost your mood, and overall, improve your quality of life, how can you not be proactive to find out if  your status is “D” light full or “D” eficient?

Jennifer McDaniel

Jennifer McDaniel is a Registered Dietitian, Media Spokesperson, and co-author of Prevention's Mediterranean Table Cookbook. She and her team of Registered Dietitians aim to help their clients go further, make change last, and unlock their potential. She lives in St. Louis, MO with her husband, and three young sons. If you are interested in working with Jennifer, please visit our contact page.