Common Deficiency Weakens Your "Cancer Barrier" (Are You at Risk?)

By Dr. Scott Olson, ND Posted June 9, 2025

If you’re over 50, you likely know that colorectal cancer is a serious threat.

It’s one of the most common—and deadliest—cancers affecting older Americans.

But what if I told you that a common vitamin could slash your risk up to 58 percent?

A new study once again confirms that this inexpensive nutrient is one of our most potent weapons against this devastating disease…

In a comprehensive new study published in the journal Nutrients, researchers confirmed a significant link between vitamin D levels and colorectal cancer risk.

After reviewing data from 50 studies on vitamin D and colorectal cancer, scientists found that those with the highest vitamin D intake (80 ng/mL) had a 25 percent decrease in colorectal cancer risk compared to those with the lowest (10 ng/mL).

But the results from the Nurses’ Health Study—an extensive, long-term U.S. study investigating risk factors for chronic diseases in women—were even more impressive.

Women with the highest vitamin D intake had a 58 percent lower risk of colorectal cancer compared to those with the lowest. In other words, having adequate vitamin D levels can more than cut your risk by HALF!

Other research has found high doses of D can also slow the progression of the disease.

So, what’s the secret behind this humble vitamin’s cancer-fighting powers?

Scientists say vitamin D protects colon health in two crucial ways:

• First, it’s a potent immune system regulator, enhancing the function of the spleen and lymph nodes and boosting T-cell activity, the white blood cells that fight infection and cancer.
• Second, vitamin D supports gut receptors that improve calcium absorption and strengthen your intestinal barrier. This allows your gut to absorb nutrients while keeping out harmful bacteria that could trigger inflammation and damage.

When you are vitamin D deficient, your intestinal barrier weakens, setting the stage for the cellular changes that can lead to colorectal cancer.

According to experts, about 35 percent of U.S. adults are vitamin D deficient. That’s more than one in three Americans walking around with suboptimal levels of this cancer-fighting nutrient.

The good news is boosting your vitamin D is relatively simple. Here are a few ways to increase your levels:

• Seek out sunshine: Just 10 to 15 minutes of direct sunlight on your arms and legs several times a week will allow your body to produce more vitamin D. However, this process becomes less efficient as we age, so additional steps might need to be taken to boost your levels.
• Eat vitamin D-rich foods: Fatty fish, including salmon, mackerel, and tuna, are excellent vitamin D sources. Egg yolks, cheese, and mushrooms also contain smaller amounts.
• Take a supplement: For many older adults, especially those in northern climates, a vitamin D supplement may be necessary to reach optimal levels. Look for vitamin D3 (cholecalciferol), which is more absorbable than D2.
• Combine with K2: For better absorption and utilization, consider a supplement that pairs vitamin D with vitamin K2.
• Factor in weight: If you’re overweight, you may need more vitamin D to reach adequate levels, as it can get diluted in body fat.

Remember, while this research is promising, vitamin D is just one part of a comprehensive approach to colorectal cancer prevention. Regular screenings, a healthy diet rich in fiber, regular exercise, and avoiding tobacco and excessive alcohol are all critical components of reducing your risk.

P.S. Colon cancer “cover-up” puts YOU at risk!

Source:

Fekete M, Lehoczki A, Szappanos Á, Zábó V, Kaposvári C, Horváth A, Farkas Á, Fazekas-Pongor V, Major D, Lipécz Á, et al. Vitamin D and Colorectal Cancer Prevention: Immunological Mechanisms, Inflammatory Pathways, and Nutritional Implications. Nutrients. 2025; 17(8):1351. DOI:10.3390/nu17081351

Written By Dr. Scott Olson, ND

Nearly 25 years ago, failed mainstream medical treatments left Dr. Olson in constant pain – and his health in ruins. And that’s when he did something REVOLUTIONARY. He began his career in medicine – and dedicated his life to uncovering the true, underlying causes of disease.
Through his innovative medical practices in Tennessee and Colorado, Dr. Olson has helped cure countless seniors from across America of arthritis… heart disease… diabetes… and even cancer. All without risky prescription drugs or painful surgeries.

View More By Dr. Scott Olson, ND