Omega 3 in wild and farmed fish

Dr Paul Clayton’s Health Newsletter March 2014

“Wild fish are high in omega 3 because of the marine algae they eat; farmed fish contain few, if any, omega 3s.”

According to the Food & Agriculture Organisation (FAO), we are consuming an average of 17 kg of fish per person per annum (FAO#1), and the figures are increasing. But where will tomorrow’s fish come from?

Since 1980 the global volume of wild-caught fish has increased by a third, from 69m to 93m tonnes.

Over the same period, aquaculture has increased nearly 11-fold, from 5m to 63m tonnes (FAO#2). This reflects the cost-efficiency of fish farming. If you want to produce animal protein for human consumption, it is cheaper to raise fish than chickens. Feed conversion ratios are better because fish don’t need to be kept warm and they don’t need to grow strong (weight-bearing) skeletal systems.

By 2030, the FAO predicts that two-thirds of all fish in the food chain will be farmed (FAO#3), making an ever-increasing contribution to our protein requirements—IF the current epidemics of aquaculture infections can be controlled and contamination problems resolved (Hites et al ’04).

But something is missing …

Wild cold-water fish provide not only protein, but also something much rarer: the omega 3 fatty acids EPA and DHA—essential nutrients that provide us with anti-inflammatory protection and are built into the fabric of our bodies and brains. Wild fish do not make omega 3s, but obtain them from marine algae at the base of the cold water marine food chain. Farmed fish contain few, if any, omega 3s.

There are not enough fish in the sea to feed every human even the minimum 250 mg intake of omega 3s that many countries now recommend, and not nearly enough to provide the 5 grams or more that science indicates is needed for optimal health (Brunner ’06).

Fish farming will not be the answer unless fish feed manufacturers up their game considerably. The Chinese government is concerned about their children’s health and is taking this very seriously (Crawford ’14), but the EU is sadly, and as usual, far behind the curve.

Brunner E. Oily Fish and Omega 3. BMJ.Apr 1;332(7544):739-40.

Crawford MAA. Personal communication 2014

FAO#1. State of the world’s fisheries and aquaculture. FAO 2nd Feb 2011



Hites RA, et al. Assessment of Organic Contaminants in Farmed Salmon. Science 303 (5655). 226-229, 2004.