Omega 3 fatty acids may slow progression of arthritis

Omega 3 fatty acids have been shown to be better at keeping joints healthy than omega 6 fatty acids in a study published in the Annals of the Rheumatic Diseases. The studies on mice suggest that unhealthy dietary fats – not just obesity – may contribute to worsening osteoarthritis.
“Our results suggest that dietary factors play a more significant role than mechanical factors in the link between obesity and osteoarthritis,” says Dr Farshid Guilak, the study’s senior author.
Obesity is one of the main risk factors for osteoarthritis, but the mechanisms linking these conditions are not fully understood. It has been assumed that increased weight wears the joints out, but this doesn’t explain why arthritis is also found in hands and other joints that don’t bear weight.
Dr Guilak and his colleagues have studied factors other than body weight to determine their effect on arthritis, and in a previous study of obese mice, found that the lack of appetite hormone leptin predicted whether the mice had arthritis.
“This made us think that maybe it’s not how much weight you gain, but what you eat,” he says.
In the current study, the researchers focused on mice with osteoarthritis of the knee caused by injury to the joint (arthritis resulting from trauma or injury is thought to account for 10–15% of all cases of arthritis).
The mice were fed one of three high-fat diets:

  • Rich in saturated fat (usually comes from animal sources and known to raise cholesterol levels)
  • Rich in omega 6 fatty acids (often found in corn oil, soybean oil, nuts and seeds and thought to be a healthier source of fat)
  • Rich in omega 6 fatty acids but supplemented with a small amount of omega 3 fatty acids. (commonly found in fish or fish oil supplements and often touted as “healthy fat” given their heart-healthy and anti-inflammatory properties).

The researchers found that arthritis was significantly associated with the mice’s diets, but not with body weight. The mice that ate diets high in saturated fat or omega 6 fatty acids experienced significant worsening of their arthritis, while mice consuming a small supplement of omega 3 fatty acids had healthier joints.
“While omega 3 fatty acids aren’t reversing the injury, they appear to slow the progression of arthritis in this group of mice,” Dr Guilak outlines. “In fact, omega 3 fatty acids eliminated the detrimental effects of obesity in obese mice.”
The researchers are working to translate their findings to humans.
“A great next step would be to do a clinical study to look at effect of omega 3 fatty acids post-injury,” Dr Guilak says.
Click here to read the original research.