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Some fatty acids are good
Article Type: Food facts From: Nutrition & Food Science, Volume 42, Issue 1
As we are increasingly finding out not all fats are equal. There are obviously “bad” fats that everyone has railed against and tried to remove from our diets in recent years, but the idea that some fats are more than just a “necessary evil” – and are actually “good” for us. This research from the University of California, San Diego Health Sciences, published in the journal Cell, makes a clear distinction between “bad” fats (animal-derived saturated fats like lard and butter) – and “good” fats (polyunsaturated fats from plants and cold-water fish like salmon and mackerel).
The former fats are associated with increased risks of cardiovascular disease, type 2 diabetes and obesity – especially as they are widely available in all the fast fat food outlets that are everywhere, whereas the latter fats are known to produce beneficial health effects and can reduce the risk of cardiovascular disease and diabetes. In this paper, as lead researcher Michael Karin explains:
These findings not only explain the long-standing enigma regarding the differential health effects of saturated and unsaturated fatty acids, they also provide improved tools and a mechanistic framework for the potential development of dietary supplements to treat obesity, estimated to be worth billions of dollars per year.
They identified the key player in allowing both good and bad fatty acids to activate JNK as the cell membrane – which is the only structure able to discriminate between various fatty acids. They eventually identified a membrane-associated protein kinase able to account for the differential effects on this JNK activity and identified c-Src, a membrane-associated tyrosine kinase. Bad fats “push” c-Src into parts of the membranes where they reduce their fluidity and increase their rigidity, which leads to activation of JNK. Good fats prevent these changes (http://bit.ly/oH0Mu8).