Vitamin D

A Welcome Message From Dr. Lee

One of the most common questions asked by my patients is: “What vitamins and supplements should I take?”

After years of testing patients for vitamin and nutritional deficiencies and reviewing the current literature, it is obvious to me that we are not getting the nutrients we need even if we eat a well balanced diet.

It is also apparent over my 40 years of clinical experience and through reviewing the literature that many diseases are related to vitamin and mineral deficiencies.

The goal of taking appropriate vitamins and supplements is to maintain health and wellness. These vitamins and supplements can be found in our online store. Please feel free to email us if you have any questions:

What is Vitamin D?

Vitamin D is a biomodular vitamin ( a vitamin which exerts transcriptional regulation of genes at the molecular pathway level ) identified in the early 20th century is a  that controls the expression of over 1,000 genes- which is around 1/24th of the human genome. Vitamin D deficiency is widespread, and recommended doses are usually inadequate to maintain healthy levels. It is estimated that 70 percent of the population is low in vitamin D. In my practice 100 percent of my patients are very deficient and need supplementation.

What Happens if I am Deficient in Vitamin D?

Vitamin D is critical for bone health many other benefits. Vitamin D deficiency can result in:

  • poor bone health
  • reduced brain oxytocin
  • impaired executive function
  • increased inflammation
  • brain dysfunction
  • increased cancer risk
  • reduced T regulatory cells
  • increased DNA damage
  • acceleration of aging
  • possible link to autism

What are the Benefits of Vitamin D?

Healthy and Strong Bones

Vitamin D is used by the body to promote calcium absorption. Since our bones are made of calcium, Vitamin D is critical for healthy bone growth and maintenance. In fact, without sufficient vitamin D, bones can become thin, brittle, or misshapen. Together with calcium and K2 vitamin D also helps protect older adults from osteoporosis.


Telomeres are a biomarker of aging. As we age our telomeres on our DNA shorten. You could think of telomeres as similar to the plastic tips on shoe laces. These protect our DNA and keep it from “unraveling”. A large study of female twin pairs found that increased vitamin D levels correlated with increased telomere length in white blood cells. This increased DNA damage can be the equivalent to as much as five years of biological aging. (Sources: Liu, JJ, et al. Plasma vitamin D biomarkers and leukocyte telomere length. American journal of epidemiology,,

Cancer Prevention

The benefits of proper Vitamin D levels continue. In fact, the National Institute of Health found that: "Inflammation is a critical early step in the carcinogenesis cascade for many cancers, and the ability of vitamin D to exhibit anti-inflammatory effects on cancer cells by down-regulating the pro-inflammatory pathways, such as cyclooxygenase-2, may contribute to cancer inhibition" (Moreno et al., 2005).” (Source:

Vitamin D is Neuroprotective

Vitamin D deficiency has been linked to several neurological diseases, including Parkinson’s. In the study referenced below a systematic review and meta-analysis were conducted on observation studies that reported the association between blood vitamin D levels and Parkinson’s disease. The results indicated that patients with vitamin D deficiency experienced a twofold increased risk of developing Parkinson’s disease. Other evidence reveals links of Vitamin D deficiency to MS and ALS (Source:

Vitamin D and Autism

In a 2014 study by authors Patrick and Ames presented evidence that vitamin D activates the transcription of the serotonin-synthesizing gene tryptophan hydroxylase 2 (TPH2) and represses the transcription of tryptophan hydroxylase 1 (TPH1). This proposed mechanism explains 4 major characteristics associated with autism: low concentrations of 25(OH)D3, the high male prevalence of autism, and the presence of maternal antibodies against fetal brain tissue. 


  2014 Jun;28(6):2398-413. doi: 10.1096/fj.13-246546. Epub 2014 Feb 20.

Vitamin D and Depression

Several studies have linked low vitamin D to depression and anxiety. Correlation is found at all ages and in both men and women. (Sources:,


What are Sources of Vitamin D?

After hearing the wide range of benefits of Vitamin D, you might be wondering, where do we get it? There are three sources of Vitamin D:
  1. Some foods such as egg yolks & fish have natural amounts
  2. Our skin produces Vitamin D when exposed to sunlight (specifically UVB rays)
  3. The final option is to supplement our intake.

It’s important to note that there are two kinds of Vitamin D: D2 and D3:

  • D2 is usually artificial and added to foods to fortify them
  • D3 is natural and found in some foods, naturally created by your skin when exposed to sunlight

Both D2 and D3 can be found in Vitamin D supplements. The Lee Clinic offers Vitamin D3 supplements.

What Contributes to Vitamin D Deficiency?

If you eat a lot of eggs and fish and get enough sun, you might be thinking “Great! I surely have enough Vitamin D!”

However, you might be surprised to know that Dr. Lee has treated landscapers (who surely get plenty of sun) who are deficient in Vitamin D. In fact, nearly all his patients over the years have tested and shown low levels of Vitamin D.

Why am I Low in Vitamin D even if I Spend so Much Time Outside and Have a Good Diet?

Many factors are attributed to low levels of Vitamin D, including:

  • Age - as we age, our levels drop
  • Limited exposure to the sun - our lifestyle often includes spending most of our time indoors. (Areas in the Pacific Northwest are particularly low in Vitamin D)
  • Sunscreen - blocks UVA B which is responsible for Vitamin D levels
  • Melanin - the darker your skin, the more you are protected against UVB rays, and therefore are likely to have lower levels of Vitamin D3
  • Obesity - Vitamin D is a fat soluble vitamin and gets “stuck” in fat. Therefore any Vitamin D that you take or have in your system is not bioavailable (i.e. cannot be used by your body).

Many studies confirm Dr. Lee’s findings. For example, this study explains: “Vitamin D deficiency is widespread, and recommended doses are usually inadequate to maintain healthy levels.” (Source:

How Much Vitamin D Should I Take?

The recommended daily allowances for vitamin D set by the Food and Nutrition Board are very conservative, and in my practice I find 5,000 IU/day is a good amount for maintenance. But it is important to note that you should test ideally your Vitamin D levels before and after supplementation to know if you are in the right range.

In my practice, I find nearly all of percent of my patients are low in vitamin D when tested initially. After taking 5,000 IU of Vitamin D3 daily for six months and testing them again, nearly all have healthy levels of Vitamin D.

Is it Possible to Have Too Much Vitamin D?

It’s possible to take too much Vitamin D, but is rare. A blood test result of over 150 ng/ml is potentially toxic. If you have levels that high you would need to also have a test to measure your blood calcium. These extremely high levels are associated with toxic side effects of hypercalcemia and require the attention of your medical provider.

While this is not an absolute guideline, studies have indicated that for most people to be toxic they would need to take more than 10,000 IU per day for at least three months, or doses of 50,000 IU for several weeks, or if they have taken more than 300,000 IU in a 24 hour period.

What kind of Vitamin D supplements should I take?

I recommend 5,000 IU of Pharmaceutical Grade Vitamin D3. In fact, on our website and in our clinic we offer only pharmaceutical grade vitamins and supplements.

What does Pharmaceutical Grade mean?

Pharmaceutical grade vitamins contain the purest form of nutrients and offer maximum absorption. Pharmaceutical grade vitamins must exceed 99 percent purity and contain no binders, fillers, excipients, dyes, or unknown substances.

Fewer than 3 percent of the products on the market are pharmaceutical grade.

What are the benefits of Pharmaceutical Grade vitamins?

You will feel better on pharmaceutical grade products due to better bio-availability. Pharmaceutical grade vitamins can only be produced in FDA registered facilities that follow GMP protocols.

Therefore all of the Lee Clinic Vitamins and Supplements are are based on firm scientific foundation and medical research and are manufactured in a GMP 9000 registered facility certified by both NSF (R) International, and ISO 9001:2000. These certifications attest to the fact that a third party verifies manufacturing, packaging, warehousing, and distribution of dietary supplements consistent with standards proposed by the US Food and Drug Administration. You are assured that our products have independent verification that products meet label content claims and do not contain contaminants such as unintended microbes or lead and heavy metals.

It is apparent that many products that are offered in health food stores and large chains, do not meet these standards. Recent cease and desist orders against large chains in the past year attest to the fact that all supplements are not created equal. (Source:

Are there other Vitamins and Supplements I should Take?

“What vitamins should I take?” is probably the most common question I’ve been asked by my patients in over 40 years of medical practice.

It turns out that Vitamin D is just one of many vitamins that nearly all my patients need. To address this I created the Physician's Daily Basic Pack, which includes Vitamin D, as well as other critical pharmaceutical grade vitamins and supplements, including: Vitamin A, C, D3, E, K, thiamine, riboflavin, niacin, vitamin B6, folate, B12, Biotin, Pantothenic Acid, Iodine, and magnesium bisglycinate chelate.


  • Vitamin D Fact Sheet for Health Professionals
  • Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: National Academy Press, 2010.
  • Hypercalcemia, MedicinePlus, NIH.