Omega 3 Fatty Acids and Vitamin D Supplementation Cancer Risk

Do Omega 3 and vitamin D supplementation lower colorectal cancer risk?

The VITAL (Vitamin D and Omega-3 Trial) trial was published recently in JAMA Oncology:

Study Design

Patients were given daily omega-3 fatty acid supplemention (EPA 460 mg, DHA 380 mg) and Vitamin D3 (2000IU) daily or placebo in apparently 25,871 healthy individuals (mean age 67 years).

After a median follow-up of 5.3 years (range 3.8-6.1 years):

  • There were 294 cases of colorectal adenomas in the omega-3 group and 301 cases in the control group (OR, 0.98; 95%CI, 0.83-1.15)
  • There were 174 cases of polyps in the omega-4 group and 167 in the control group (OR, 1.05; 95%CI, 0.84-1.29)
  • A beneficial association of supplementation with lower adenoma risk in the African American population (OR, 0.59; 95%CI, 0.35-1.00)
  • There was a lower risk of adenomas in people with low omega-3 levels at baseline (OR, 0.76; 95%CI, 0.57-1.02)

Bottom Line:

  • Supplementation with marine ω-3 fatty acids, 1 g per day, was not associated with reduced risk of colorectal cancer precursors.
  • A potential benefit of this supplementation for individuals with low baseline ω-3 levels or for African American persons requires further confirmation.
  • Although many patients supplement with Omega-3 fatty acids and vitamin D, there does not appear to be a reduced risk of polyps or colorectal cancer