Quebec City, May 9, 2007 -- A research team led by Carole Thivierge, from Universit Lavals Institute of Nutraceutics and Functional Foods, shows that omega-3 fatty acids from fish oil have a positive effect on the metabolism of muscle proteins. This finding, published in a recent edition of the Journal of Physiology, could have significant implications in the fields of animal farming as well as human health.
In mammals, the ability to use nutrients from food and convert them into muscle proteins decreases with age. Though the exact cause of this phenomenon is still unclear, insulin resistance of aging muscle cells has been suggested as a possible answer.
Since omega-3 fatty acids are known to improve glucose metabolism in people and animals showing insulin resistance, the researchers decided to test whether omega-3s could also influence protein metabolism.
To do so, they added supplements containing either omega-3s from fish oil or a mixture of cottonseed and olive oils without omega-3s to the regular diet of steers. After five weeks, animals with the marine omega-3 diet showed increased sensitivity to insulin which, in turn, improved protein metabolism: twice the amount of amino acids was used by their bodies to synthesize proteins, especially in muscles. So it appears that omega-3 fatty acids added to the steers diet replaced other fatty acids in muscle cells and improved their functioning.
This finding could have significant implications in the field of animal farming, according to Thivierge, also a professor in Universit Lavals Department of Animal Sciences, who undertook this study in order to find an alternative to hormonal growth stimulation in beef cattle.
At 4 to 6 months of age, calves become less efficient at converting food into muscle mass, which has a negative impact on farming profitability. "Adding fish oil to their diet could prevent this decline by restoring insulin sensitivity in aging animals,"
Contact: Jean-Franois Hupp