Research

Hormonal

A lower omega-6 to omega-3 ratio (specifically 2.5:1) reduces rectal cell proliferation in patients with colorectal cancer, whereas a higher ratio (4:1) with the same omega-3 amount has no effect.

If you have colorectal cancer or are at high risk, aim for a very low omega-6 to omega-3 ratio of 2.5:1. This requires significantly reducing omega-6 oils (corn, soy, sunflower) and increasing omega-3 sources (fatty fish, flaxseed). Simply taking fish oil without reducing omega-6 may not provide the same protective benefits against cell proliferation.

ModerateQualifiesMEDIUM confidence
A ratio of 2.5/1 reduced rectal cell proliferation in patients with colorectal cancer, whereas a ratio of 4/1 with the same amount of omega-3 PUFA had no effect.
Artemis P. Simopoulos · Experimental Biology and Medicine · 2008

Why this rating

Based on a specific study cited in a review, not a large-scale consensus guideline.

Source

The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cardiovascular Disease and Other Chronic Diseases

Artemis P. Simopoulos · Experimental Biology and Medicine · 2008

DOI 10.3181/0711-mr-311

narrative_reviewCited 2,886×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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