Sunlight provides us with the source to make vitamin D3.

An article caught my attention today as I was scanning health and wellness topics. The headline stated that lack of sunlight is linked to colon cancer. The underlying suspicion is that sunlight equates to more vitamin D and that lack of vitamin D leads to cancer.

Article Researchers at the University of California, San Diego surmise that higher levels of vitamin D reduce the risk of colon cancer. Their analysis does not say that the lack of vitamin D causes cancer; it is a focal point that data from 186 countries indicate. When you live nearer the equator, the likelihood of developing colon cancer is less. What happens when you live in that part of the world – more access to sunlight.

The Study This week, the journal BMC Public Health published an article that examined the association of UVB (ultraviolet B) radiation from sunlight (the kind that causes our skin to create vitamin D) and the rates of cancer for people living to their mid-70s.

The study admitted that it is impossible to determine the cause of colon cancer because of many variables – age, life expectancy, skin pigmentation, smoking, diet, vitamin supplements, clothing, air pollution, sunscreens, and more. However, they could differentiate some of the variables and steer in on vitamin D as a primary agent that reduces the risk of colon cancer. Sunlight (vitamin D) appears more significant after reaching 45-50 years of age.

Vitamin D Vitamin D is found in the human body in two forms – vitamin D2 (VD2), also called ergocalciferol, and vitamin D3 (VD3), also known as cholecalciferol. Vitamin D assists the body in using calcium and phosphorus.

Several epidemiologic studies confirm that cancer incidence and death rates are lower in people living in southern latitudes. Strong experimental evidence suggests that vitamin D3 is responsible for the lower risks of cancers. Laboratory animal analyses show that VD3 is responsible for cellular differentiation that prevents or slow cancer formation and growth. Apoptosis or stimulating cancer cell death is also increased in the presence of VD3. Angiogenesis, or the reduction in tumors forming their own blood vessels, is also degraded with higher levels of VD3 in the body.

Details & Stats The previous government article stated that 80% of Americans had adequate levels of VD3. However, this government study uses a different measure for adequate, and 40% of Americans are delinquent. Who is right? It depends on what standard you use for adequate.

The standard has changed over time, and some agencies continue to use older limits. In nearly every article I read about VD3 and recommended daily allowance (RDA), the suggested amounts do not allow the body to build internal levels of VD3 to anywhere near what the newest standards recommend.

If your VD3 levels are below 50 nmol/L, you are probably delinquent. The older standard used 20 nmol/L as the beginning edge of delinquency. However, there is a significant difference between 20 nmol/L and 50 nmol/L. Using the RDA for VD3 of 4,000 IUs/day (100 μg), there is no way a person would ever achieve VD3 levels of 50 nmol/L.

Years ago, I started increasing my supplemental VD3. At my annual physicals, I requested a VD3 blood test as part of my blood testing. Over time, I raised my daily IUs of VD3 and observed that it took around 10,000 IUs/day to get to the 50 nmol/L. Yes, everyone is different, and I might process VD3 more efficiently than others.

Regardless, I would increase my VD3 in the winter and reduce it in the summer. When the pandemic started, I made a conscious decision to maintain my winter VD3 daily levels at 20,000 IUs/day throughout the summer as additional protection from the virus. (Lots of articles written by me and others on VD3’s ability to block the ACE2 receptor to prevent the viral spike from connecting to cells in our bodies).

My most recent VD3 test result was 108 nmol/L. Many doctors go blitzo when they see VD3 readings above 100 nmol/L. My doctor is not one of them. Many people take 50,000 IUs/day to stave off symptoms from multiple sclerosis (lots of testimonial data on that topic available). I know people taking 100,000 IUs/day and have not problems. VD3 toxicity is real, but it is not approached taking more than 4,000 IUs/day as many health professionals believe.


Regardless of where you live, supplemental VD3 is available to boost VD3 levels in your body. If you are not getting a VD3 test annually, request one. They are not expensive. I quickly checked local pricing for VD3 testing, and several reported the test for under $100.

My wife’s oncologist wanted her to keep her VD3 levels between 80 nmol/L and 100 nmol/L to increase the chemo drugs’ effectiveness and prevent metastasis. Unfortunately, taking 4,000 IUs/day will never get your body to 80 nmol/L.

So, most of the time (except for the pandemic season), my VD3 runs just above 80 nmols/L.
It is an easy test and tells you a lot about your body. Seriously consider adding it as a regular test as part of your overall blood work at your next physical.

Live Longer & Enjoy Life! – Red O’Laughlin –


3 Responses

  1. Red – Thanks for this information. My next annual physical is in October and I’ll touch base with you on what additional tests I ought to include. Hiett

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