The vitamin every colon cancer patient should be taking

There’s certainly nothing new about vitamin D’s role in fighting colon cancer. In fact, in my very first medical textbook in 1989, Nutrition and Cancer Prevention: Investigating the Role of Micronutrients, I made sure to include a chapter on “Vitamin D and Colon Cancer,” by Dr. Michael Wargovich.

Since then, there have been many studies on this topic—most recently with the SUNSHINE trial.

This study included 139 people with metastatic colon cancer—cancer that has spread beyond the colon. Treatment for this advanced-stage cancer usually involves chemotherapy.

Researchers wanted to find out how vitamin D affected cancer progression in these subjects. So they divided them into two groups.

The first group (“high-dose”) took 8,000 IU daily for 14 days, followed by 4,000 IU daily.

The second group (“low-dose”) took 400 IU daily for the duration of the study.

Both groups also received standard cancer chemotherapy.

After 23 months of follow-up, researchers found that cancer progression in the high-dose group was halted for an average of 13 months, while the low-dose group saw an 11-month delay. Members of the high-dose group were also less likely to die during the follow-up period.

So it seems that the high-dose group fared better, partially because vitamin D helped counter some of the toxic effects of chemotherapy—as well as having direct anti-cancer activity.

We’re always hearing about the “dangers” of too much vitamin D. But these supposed perils pale in comparison to the real toxicity of cancer chemotherapy.

(And as I reported in a recent Daily Dispatch, many patients diagnosed with cancer die from the chemotherapy itself—within the first 30 days!) So if “high dose” vitamin D helps offset those effects, it’s certainly well worth incorporating into any cancer treatment regimen (not just colon cancer).

But the fact is, these supposedly “high” doses aren’t actually high at all.

Busting the “high dose” myth

The SUNSHINE trial also gave us some interesting data on vitamin D dosages. At the start of the study, only 9 percent of all participants had blood levels of vitamin D in the “sufficient” range (50 to 60 ng/mL).

This is typical of the population in general, as most everyone is deficient or insufficient. But it’s even more typical of a population of patients with cancer—since optimal vitamin D levels markedly reduce the risk of getting cancer and other chronic diseases in the first place.

At the end of the study, researchers found that the low-dose group had no substantial change in their vitamin D blood levels. But those in the high-dose group reached the sufficient range soon after the study began—AND maintained those optimal levels as they continued to take vitamin D.

So you may be wondering: How was this too high of a dose if it’s the only dose that actually helped people reverse their D deficiency?

Well, it wasn’t “too high.” In fact, plenty of science shows that, contrary to what the mainstream tells you, a dose of 4,000 IU or even 8,000 IU daily is actually too low to help you reach optimal blood levels of vitamin D, or optimal health, for that matter.

Which is why I recommend 10,000 IU daily of a high-quality vitamin D3 supplement to help prevent and reverse colon cancer and many other chronic diseases.

You can now even find vitamin D in a convenient liquid form, together with the potent marine carotenoid astaxanthin. (To learn about my personal recommendations, visit


1“SUNSHINE: Randomized double-blind phase II trial of vitamin D supplementation in patients with previously untreated metastatic colorectal cancer.” Journal of Clinical Oncology 35, no. 15_suppl (May 20 2017) 3506-3506.