Tuesday, October 5, 2010

Vitamin D3 vs. D2 - What You Need to Know

Many natural doctors, along with nutritionists and experts in the health field have long known the importance of vitamin D. In the past 2 years however, Vitamin D has finally come into the spotlight. Research has found that not only does Vitamin D play a critical role in your overall health and well being, but optimal levels are necessary in order to prevent many cancers, osteoporosis, Rickets, Seasonal Effective Disorder and depression.  Vitamin D also plays a huge role in preventing many other illnesses including the common cold and flu.

In the past 2 weeks, I have run into 2 people who had their Vitamin D levels tested and were placed on (or prescribed) Vitamin D2. I felt it necessary to write this post because people need to understand the difference between the different forms of Vitamin D in order to achieve optimal levels from supplementation.

Many people do not realize that there are several forms of Vitamin D. There is Vitamin D1, D2, D3, D4 and D5. The two major forms of vitamin D are vitamin D2 (ergocalciferol) and vitamin D3 ( cholecalciferol). Pharmacopoeias have officially regarded these 2 forms as equivalent and interchangeable, yet this presumption of equivalence is based on studies of Rickets Disease prevention in infants conducted 70 years ago.

Now that we have the 25-hydroxyvitamin D test as a measure of vitamin D, not only can we see what level of Vitamin D we have in our bodies, we can see a quantitative measure of the biological response to vitamin D through administration/supplementation. Because of this, we have learned that Vitamin D3 is far superior when it comes to absorption. You see, D2 is a synthetic product made by exposing certain plants to ultraviolet radiation. D2 is not what the body naturally uses. D2 was produced in the 1920's. The process was patented and licenced to pharmaceutical companies which then led to a medicinal preparation called vitamin D2 or Viosterol. Unfortuneatly, to this day, the major preparations of vitamin D for presctiption use in North American are in the form of vitamin D2. Although D2 can be used to prevent the vitamin D deficiency disease, rickets, in humans (when given in massive amounts), clinicians have reported disappointing results when using vitamin D2 to treat vitamin D deficiency.

Please -- if you supplement with vitamin D3, have your vitamin D levels tested routinely to ensure you do not overdose with it. You and your physician need to be aware of your vitamin D levels so you can adjust your supplementation accordingly. This is a customized approach -- not a one-size-fits-all.

Having said that, studies suggest that most people are deficient in vitamin D -- not overdosing with it. Also, just in case you did not know, the milk you drink is fortified with D2, not D3.

As the cold and flu season approach us, I strongly encourage everyone to get their Vitamin D levels checked (moms and dads, this includes your children too). If your kids are not pill takers, there are wonderful droplet forms of vitamin D3 available to give to your children. I use them in my own home.

When it comes to health and medicine these days, you must be your own advocate. Althougth time consuming, extensive reasearch has become absolutely necessary.

I like to use this chart from Dr. Mercola to compare my family's vitamin D test results with. As a cancer survivor, I strive for levels between 70-100 ng/ml.



  1. It's wonderful that you are sharing the facts and importance about Vitamin D! This could be the single most discussed topic with my DO. He is big on this one.
    Most Americans are vitamin D deficient, and have no idea of the impact.

  2. Keep spreading the word Lisa and hopefully we can get everyone back up to optimal levels.