Fish oil goodness

New research from the University of Bristol confirms what our mothers – and their mothers – knew: fish oil is good for our joints. The study, published in the journal Osteoarthritis and Cartilage, and funded by Arthritis Research UK, looked at the effects that a diet rich in omega-3 fatty acids had when fed to guinea pigs.

Guinea pigs do naturally develop osteoarthritis, and as the tests show, fish oil works for them. The results – a 50 per cent reduction in disease markers compared with a standard diet – mark a major step forward. This shows that omega-3 fatty acids may help slow down the progression of osteoarthritis. It may even help prevent it developing at all.

“We’re quite excited about the result,” said lead researcher Dr John Tarlton, from the Matrix Biology Research Group at the University of Bristol’s School of Veterinary Sciences. “ As scientists we’re not supposed to have a preferred outcome, we’re supposed to be completely unbiased by this, but from the point of view of Arthritis Research UK, who have funded this research, I’m quite pleased that it’s got a positive result.”

“I think it’s quite a significant discovery really. This is the first time that any drug or any dietary supplementation has actually been shown to affect the disease process, and that you can prevent susceptible individuals from getting the disease.”

Fish oil

“All guinea pigs develop osteoarthritis, and they do this at a relatively young age, from about 15 weeks through to 30 weeks of age. In this study we fed the guinea pigs omega-3 fatty acids from 10 weeks old. By the time they were 30 weeks there was a significant and clear difference in the markers for the disease between those that had received omega-3 fatty acids and those that hadn’t.” Classic early signs of the condition, such as the degradation of collagen in cartilage and the loss of molecules that give it shock-absorbing properties, were both reduced with omega-3.

“The possibility that omega-3 fatty acids could prevent osteoarthritis from developing has been a tantalising one,” said Professor Alan Silman, Medical Research Director of Arthritis Research UK. “Some limited, previous research in dogs has suggested that we were a long way away from understanding the potential use in humans. However, this current research in guinea pigs is exciting as it brings us closer to understanding how omega-3 might fundamentally interfere with the osteoarthritis process, and that it could potentially be taken as a treatment.”

“A normal diet for humans, guinea pigs, hens and many other domesticated and farm animals, is a food chain that is based mainly on grain, wheat, soya, rice and so on, and has high levels of omega-6, but low levels of omega-3. So what we’re doing is redressing the balance,” said Dr Tarlton. “Lots of people don’t eat enough fish. Studies on western diets have shown that they tend to contain between 10 and 30 times too much omega-6 and too little omega-3.”

“If you eat lots of green vegetables and a portion or two of oily fish during the week, you may not need to supplement your diet. But most of us don’t get as much omega-3 in our diets as we should, so a supplement is probably a good idea for most people.”

The total intake of omega-3 recommended by the government is 2g a day. Most of this amount can be found in our normal diet. If you have a good diet you may not need to take extra supplements, but this does depend on how much oily fish, such as salmon, mackerel, herring and sardines you have each week. Supplement capsules usually come as either 450mg or 1,000mg of fish oil.

Osteoarthritis affects around eight million people in the UK, and is caused when the cartilage at the ends of the bones wears away and the underlying bone thickens, leading to stiff, painful joints. Currently, there is no effective treatment to slow down disease progression, and treatment is limited to pain relief and ultimately, joint replacement.