Thursday, February 25, 2016

Osteoarthritis and Omega-6 Fats (Linoleic Acid)

Well...

"...Conclusions: Linoleic acid [LA] has a pro-inflammatory effect on cartilage whereas oleic acid and palmitic acid seem to inhibit cartilage destruction. These results indicate that altered fatty acid levels may influence loss of cartilage structure in OA." 
"Monounsaturated and Saturated, but Not n-6 Polyunsaturated Fatty Acids Decrease Cartilage Destruction under Inflammatory Conditions"

There's another way to read that, of course, if one assumes that high levels of LA are not normal....

This next study is hilarious; yes, if you assume that high levels of LA (which don't exist naturally) are "normal" this would be a mystifying result:

"We report here the finding that normal, young cartilages, in distinction from all other tissues exa- mined, have unusually high levels of n-9 eicosatrienoic (20:3 cis-i5’8”) acid and low levels of n-6 polyunsaturated fatty acids (n-6 PUFA)....
"...The finding of low levels of n-6 PUFA and high levels of unusual n-9 fatty acids, characteristic of EFA deficiency, in normal cartilage is remarkable in view of the fact that normal levels of EFA are present in serum, muscle, liver, kidney, and bone of the same animals (Tables 1-4). To properly understand this finding, it is important to recognize that when tissue from an EFA-deficient animal is transplanted into a nutritionally normal recipient, the EFA-deficient tissue rapidly recovers and regains a normal fatty acid profile within a period of 5 days (19). Thus it seemed implausible that a tissue should exhibit features characteristic of EFA deficiency in an animal with normal levels of EFA in its other tissues. Yet this phenomenon was consistently seen in normal cartilage of all species so far investigated (chicken, calf, human, rabbit, and pig)." 
"Unique fatty acid composition of normal cartilage: discovery of high levels of n-9 eicosatrienoic acid and low levels of n-6 polyunsaturated fatty acids"

If high LA is not normal, but is a result of a novel diet, this study might be alarming.

Especially if we'd been seeing a rise in the incidence of injuries to cartilage....

More to come...