Questions And Answers: Vitamin D

Where do we get vitamin D? 

Vitamin D is both a vitamin that we can eat and a hormone that our body can produce.  Some foods high in vitamin D include fatty fish like tuna and salmon and dairy products.  Many foods are fortified with vitamin D.  The sun’s ultra violet B (UVB) rays trigger production of vitamin D.  Spending just a few minutes in the sun during the summer months can produce many thousands of IU’s of Vitamin D.

Why is vitamin D so important?

Vitamin D is important for 2 reasons.

1) It has a major influence on our health.  Deficiency of vitamin D has been associated with an increased risk of osteoporosis, heart disease, certain cancers, multiple sclerosis and infectious diseases.

2) Deficiency is really common.  It’s hard to get enough vitamin D from your diet.  We can make it from the sun, but in the fall and winter the UVB rays that stimulate production of D are weaker, especially if you live North of the line that connects Philadelphia and San Francisco.  Deficiency of vitamin D is really common in these people as well as African Americans, the overweight and older individuals.  Sunblock also prevents production of vitamin D from the sun almost completely.

3) How can I tell if I’m deficient? 

You can ask your doctor to do a blood test on your vitamin D levels.  A level of 30 ng/ml seems to be considered by most research sources to be ideal. 

4) How much vitamin D should I be getting each day? 

This is a bit of a controversial question.  The Institute of Medicine recently came out with a report that updated their recommendations for vitamin D.  They say that for those between the ages of 1-70, 600 IU’s of vitamin D is more than enough.  For those greater than 70, they recommend 800 IU’s.

At Harvard, they think this is a bit too low.  They generally taught us that 800-1000 IU’s was really optimal.  This goes up to 2000 IU’s each day if you are at a high risk of deficiency (darker skin, obese or older). 

Despite the lower recommendations, the Institute of Medicine stated that 4000 IU’s of vitamin D each day is a safe level.

5) What is the best form of vitamin D when supplementing?

There are generally 2 forms of vitamin D that you’ll find in supplements.  Vitamin D2, also known as ergocalciferol and vitamin D3, also known as cholecalciferol.  Vitamin D2 is more of a precursor to vitamin D, while D3 is chemically the same as vitamin D.   There is some evidence that D3 is better at raising vitamin D levels so I’d recommend that over D2.

6) So, should I supplement with vitamin D?

If you’ve read my book, read this blog or work with me privately, you know I’m not a huge fan of supplementation in general.  I strongly believe that in most cases, we should get our nutrients from our food, as nature intended.  However, vitamin D is a rare exception to this philosophy.

Throughout a good deal of our evolutionary period, humans lived at a latitude south of Florida and ran around naked.  We got a lot of sun, made a lot of vitamin D and had high blood levels of vitamin D.  Now, a huge percentage of the Earth’s population does not live in such a warm client.  Not only do we wear clothes, we wear sunblock to reduce our risk of skin cancer (which is a good thing).  Therefore, supplementing with D is probably a good idea for most of us.

I recommend a multi-vitamin by Cooper Concepts that includes 2000 IU of Vitamin D in each capsule.  I take this every other day, so I’m supplementing with about 860 IU’s each day on average.  I recommend a similar protocol for my clients.  Here’s a link to this vitamin if you are interested in ordering it or learning more about it.  (http://www.coopercomplete.com/)