Normalizing your blood levels of vitamin D can sometimes be a little tougher than you would expect. There are a number of factors that have to be taken into account when you decide how much vitamin D you need to ingest in order to bring your levels up to optimum. I am going to give you some parameters to go by as you attempt to improve your level of 25-hydroxyvitamin D3. Keep in mind that you will more than likely have to play with your supplementation of vitamin D in order to get your levels at a healthy level.

Before I give you my recommendations, I want to address a question that I get asked on a regular basis. That question concerns the safety of using a high dose of a fat-soluble vitamin, like vitamin D. Health professionals were taught that fat-soluble vitamins are toxic if taken at high doses. The study evidence, spear-headed by leading researcher/clinician Dr. Michael Holick, shows that vitamin D is extremely safe to take at many times higher than the Recommended Daily Allowance (RDA). In fact, doses as high as 200,000 IU at one time have been used without negative side-effects. This does not mean, however, that vitamin D is completely non-toxic. If you have to take a very high dose of vitamin D for a prolonged period of time, you will have to have your blood tested periodically for levels of calcium. If your blood calcium is normal you do not have to worry about vitamin D toxicity. The bottom line is that vitamin D is very safe even at high doses.

So, how do you determine if you need vitamin D and how much you should take? The answer depends upon a number of factors. First, make sure you get the right form of vitamin D tested in the first place. Do not just ask for a vitamin D test because there is a decent chance that the lab will perform the wrong test. The correct form to test is:

25-Hydroxyvitamin D3

Everybody should have levels at or above 30 ng/ml. If you have a history of, high risk factors for, or if you have autoimmune disease, diabetes, high blood pressure or cancer, you need to achieve levels between 50-70 ng/ml.

One of the main factors to take into consideration is the time of year. Since direct sun exposure causes your skin to make vitamin D, you will naturally make more during the summer than in the winter months. Also, you have to take into consideration your use of sun block. Slathering yourself up with tons of sun screen will lower your natural production of vitamin D. But, Dr. Zimmer, sunlight causes cancer! How can you suggest that people get sun exposure? I am here to tell you that sun exposure DOES NOT CAUSE CANCER! Sun damage to the skin over a long period of time is what increases risks for cancer. Sun exposure is extremely healthy for you.

In fact, studies show that patients with the deadly skin cancer, melanoma, have a better chance of surviving if they have high levels of vitamin D. Those with the lowest levels had much worse outcomes. Thus, their doctor’s recommendation to stay out of the sun actually increased their chances of dying! Additionally, a large number of melanomas occur in areas that receive little to no sun exposure. If the sun causing cancer theory were correct, these cancers would show up on the face and arms for almost everyone. They do not.

You need about 15-20 minutes of exposure on your face and arms to make adequate amounts of vitamin D during the summer. During the winter this would increase to 45 minutes to an hour! That is why vitamin D levels drop so drastically in the winter. After you get a good dose of vitamin D, go ahead and protect yourself from over-exposure.

How To Use Supplements

If your levels of vitamin D are low, you may want to consider supplementation. The form you want to supplement with is vitamin D3, not vitamin D2. The vitamin D supplements you will find on www.ZimmerNutrition.com are all vitamin D3.

Unfortunately, there are no carved in stone guidelines for vitamin D supplementation. Some people can easily increase their levels with supplementation while others will be resistant. For example, I had a patient with a 22 ng/ml level who quickly increased their level to 40 ng/ml in one month taking 2,000 IU/day. I have another patient who took 2,000 IU/day and still was below 30 ng/ml even after 2 months of supplementing. The fact is that some people have bodies that are resistant to vitamin D supplementation. In these cases we may need to use 50,000 IU/week orally or even by injection for a couple of months to finally see levels increase. Once optimum levels are achieved, we can usually then maintain these levels with lower daily doses of 2,000 IU/day for these patients.

So, what should you do? First, find out your level of 25-hydroxyvitamin D3. If your levels are mildly low (between 25-30 ng/ml) or moderately low (between 20-25 ng/ml), start by taking 2,000 IU/day of vitamin D3 with food for 6 weeks. Then get your blood re-tested and make sure they test for serum calcium levels. If your levels of vitamin D increase to between 30 ng/ml - 70 ng/ml and your calcium levels are within normal, keep taking 2,000 IU/day as a regular supplement. Remember that your levels will drop in the winter and increase during the summer. So, you may have to increase or decrease your dose depending upon the time of year. Feel comfortable playing with the amount you use.

If you are severely deficient in vitamin D (lower than 20 ng/ml), I suggest that you start with 5,000 IU/day with food. Then re-test your levels and calcium after 6 weeks. If your levels have not increased you may need to double this dose or consider injections once a week for a couple of months.