Thursday, March 22, 2012

Sunshine, Salmon, and Supplements

(A rare sunny day in Seattle)

After a much needed hiatus from the blogosphere, I’m back. Sorry, just needed a little time to finish my dietetic internship and get my RD. That’s right folks, it’s official! Sarah Seppa is a registered dietitian. SO…if you didn’t believe any of the stuff I have told you up to this point, well then you had better start listening because dietitians are the experts on food and nutrition and now I am one of them. ;-)

So this expert went to her doctor last week and had her vitamin D tested. I got the results and back the other day and my serum level was 31ng/ml. There is a disagreement in the literature stating what the acceptable vitamin D levels are, however the Institute of Medicine (IOM) recently revised the recommended dietary allowances (RDA) from 400 IU to 600 IU per day for vitamin D, to maintain serum levels at or above 50 ng/ml. This was necessary to sustain bone density, calcium absorption, and to minimize risk of osteomalacia and rickets (bone mineralization disorders related to vitamin D deficiency). So basically what I am saying is I am deficient. Deficient, you say? How can a food and nutrition expert be deficient in Vitamin D? Well I was as surprised as you since I thought I was doing a good job keeping my level up.

Here are the ways that you can get vitamin D:

Sunlight exposure at least 2 x/week from 10am-3pm for 5-30 minutes on arms and legs. But this depends on a lot of factors: If you live somewhere that sunlight is marginal (Ahem…Seattle), seasonal (only in the summer months), the angle of the sun is also important (latitude- the closer you are to the equator, the better). Sunscreen use is also a big factor. People are afraid of getting too much sun because of skin cancer, rightly so. Also, darker skin can’t convert vitamin D as easily so people of African American decent often are deficient. Additionally, as you age your ability to convert vitamin D from the sun decreases.

Okay but I have all these things covered…I’m a white chick that just lived in Houston, TX for 6 months who likes to sunbathe and run outside and only uses sunscreen on her face. And I’m not THAT old…32 is the new 22, right?!

(Sunbathing in Houston while studying for the RD exam)

Here is another way you can get vitamin D: Take a supplement. WAIT?! What about food, you say? Normally I’d be with you on this but here are the best food sources of vitamin D:

Salmon (canned w/ bones) 2oz = 343 IU

Sardines (canned w/ bones) 2 oz = 150 IU

Milk 8 oz = 100 IU

(Fink HH, Burgoon LA, Mikesky AE. Practical Applications in Sports Nutrition. 2nd Ed. Sudsbury, MA: Jones and Bartlett; 2009.)

Now if the IOM is recommending 600 IU a day that means you would have to eat 3.5 ounces of canned salmon (plus the bones) or drink 6 glasses of milk to get the RDA!

Okay now let’s back up a second… I WAS taking a supplement. I was taking 2,000 IU/day. Which begs me to ask…is the recommendation of 600 IU enough to keep levels above 50 ng/ml?

(Delicious salmon dinner this past weekend with beet salad and cream of asparagus soup, made creamy with oatmeal!)

So, for now my doc is recommending 5,000 IU a day so that is what I’ll be doing. I’ll also be getting out into the sun as much as possible and eating lots of salmon because I love it. I’ll also have my levels tested in another 6 months to see if they are back up in the desirable range. I highly recommend having your levels tested, even if you think you are doing enough to keep your vitamin D up. Another note…don’t mega dose on your supplement unless you have instructions from your doctor to do so. And for now… get out and enjoy the sunshine. Unless you live in Seattle of course, but then you can always eat lots of salmon!