Omega-6/3 ratio

The ratio of omega-6 to omega-3 in erythrocytes. In a Western diet the ratio is markedly higher than in traditional diets. How it is to be read is set out in your findings report.

What the omega-6/3 ratio shows

The ratio sets all omega-6 fatty acids – mainly linoleic acid, dihomo-gamma-linolenic acid and arachidonic acid – against all omega-3 fatty acids such as ALA, EPA, docosapentaenoic acid and DHA, measured in the membranes of red blood cells. The two families cannot be converted into each other in the body, but they use the same desaturases and elongases and compete for the same membrane positions. The ratio therefore describes the overall balance of the raw material store from which membrane properties and lipid messengers arise. Unlike the EPA/AA ratio, it also covers the short-chain precursors and DHA, which is particularly needed in nerve tissue and the retina.

Low omega-6/3 ratio – what happens in the body?

A low ratio shows a comparatively high omega-3 share in the membranes. They then contain more EPA and DHA, are more supple, and on activation more resolvins, protectins and maresins and fewer messengers from arachidonic acid are formed. In the liver less VLDL is produced, which can show in lower triglycerides. Low ratios have been observed in populations with a traditionally high fish consumption. Very low values usually result from a high intake of long-chain omega-3 fatty acids; the clumping of platelets can then be dampened. Omega-6 fatty acids remain indispensable, among other things for the skin's water barrier.

High omega-6/3 ratio – what happens in the body?

A high ratio means that omega-6 fatty acids dominate the membranes. The desaturases are then mainly occupied with linoleic acid, so little EPA and DHA are formed from ALA, and on activation most eicosanoids come from arachidonic acid. In observational studies a high ratio was associated with raised inflammatory markers. The ratio alone, however, does not distinguish whether a lot of omega-6 or little omega-3 lies behind it – both produce the same ratio but have different causes. That is why the individual fatty acids such as EPA, DHA, linoleic acid and arachidonic acid are looked at as well.