A new US study suggests that higher blood omega-3 fatty acid concentrations may reduce the risk of hip fractures in postmenopausal women.
In the observational study, the concentrations of omega-3 and omega-6 fatty acids in red blood cell samples of 648 postmenopausal women with or without a history of having a broken hip were measured (1). The study results showed that higher levels of total omega-3 fatty acids (including docosahexaenoic acid, or DHA) and of two omega-3s alone (eicosapentaenoic acid, or EPA, and alpha-linolenic acid, or ALA) were associated with a lower risk of hip breaks in the participants. On the other hand, women who had the highest omega-6 fatty acid levels compared to omega-3 fatty acids had nearly twice the risk of hip fractures compared to women with the lowest ratios.
The researchers commented that clinical trials are necessary to confirm these findings until taking omega-3 supplements for the prevention of hip fractures can be recommended. However, the study findings support current recommendations to incorporate more omega-3s into the diet in the form of fish and suggest that plant sources of omega-3 may be also effective in preventing hip fractures in women. The scientists noted that it was critically important to not use data based on self-reports of food intake because of the potential bias, but to look directly at the exposure of the bone cell to the fatty acids, which is at the red blood cell level. Red blood cell levels also give an indication of long-term exposure to these fatty acids, which the scientists took into account in looking for a preventive effect. With regard to a potential mechanism for the relationships found, the researchers hypothesized that omega-3 fatty acids are believed to reduce inflam-mation, which seems to contribute to bone resorption, or the breaking down of bone associated with an in-creased risk of fractures. Broken hips are the most common osteoporosis-related fractures, with an estima-ted 350,000 occurring annually in the United States. About 20% of people die in the year following a hip fracture.
Omega-6 fatty acids are generally plentiful in a Western diet. The current typical American diet contains between 15 and 17 times more omega-6 than omega-3, a ratio that previous research has suggested should be lowered to 4-to-1, or even 2-to-1, by increasing omega-3s, to improve overall health. The primary ome-
ga-6 fatty acid in the diet is linoleic acid, which composes about 99% of Americans’ omega-6 intake and is found in corn, soybean, safflower and sunflower oils.