Colorectal cancer risk reduced by this common vitamin, study suggests

Vitamin D is widely known for boosting bone health, muscle strength and immune function, but it also has a range of other benefits - including cancer prevention.

Hungarian researchers conducted a meta-analysis of 50 previous studies that included more than 1.3 million participants, focusing on vitamin D's potential effects on cancer risk, immunity and inflammation.

"Our research clearly supports the strong correlation between 25-hydroxyvitamin D (the primary form of vitamin D) levels and cancer outcomes."

Vitamin D has been shown to reduce inflammation, promote the death of cancer cells, inhibit tumor growth and enhance immune response, the researchers found. 

"These mechanisms significantly influence the pathophysiology of colorectal cancer," Varga noted. 

"The results suggest that the effect of vitamin D may depend on factors such as the dosage, the individual condition of the patients and the duration of treatment," Vargas added.

The American Cancer Society (ACS) has previously referenced studies suggesting that vitamin D could lower cancer risk, particularly colorectal cancer.

"However, large studies have not found that vitamin D supplements lower the risk of colorectal polyps (pre-cancerous growths) or cancer," the ACS stated on its website.

One important limitation of the research is that the studies included in the analysis used different vitamin D dosages and involved patients at various stages of cancer, the authors noted. 

"The optimal dosage should be tailored to the individual's health condition and current vitamin D levels." 

For physicians, the researchers suggest routinely measuring and supplementing vitamin D levels for both prevention and treatment purposes.

"The molecular mechanisms of vitamin D - such as the regulation of oncogenes (mutated genes that can lead to cancer) and inhibition of tumor progression - require further scientific investigation."

As the effect of vitamin D is closely linked to the patient's condition, the doctor said, treatment recommendations should be personalized.

It can also be obtained from dietary sources, according to the ACS, including fatty fish and some mushrooms.

People can also take vitamin D supplements to boost their levels.

"Most Americans do not get enough vitamin D in their diets, and many have low vitamin D levels in their blood," the ACS said on its website. 

"While the role of vitamin D in lowering cancer risk is still an active area of research and debate, avoiding low vitamin D levels is recommended."