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Old Thu, Oct-11-18, 10:58
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teaser teaser is offline
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Plan: mostly milkfat
Stats: 190/152.4/154 Male 67inches
BF:
Progress: 104%
Location: Ontario
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Probably people are more familiar with the terms omega 3 and omega 6. The basic hypothesis is that the modern diet, with higher levels of omega 6 vs. omega 3 contributes to depression. There are various pathways that might be implicated in this--for instance, cannabinoids, the same class of substance that gives marijuana its effects on mood, are synthesized from fatty acids, particularly from polyunsaturated fats. Also inflammation is implicated in depression and other brain-related disorders, and omega 3's are more involved in anti-inflammatory activities where omega 6's are more involved in inflammatory pathways.

One thing about this--if the hypothesis is correct, we might have to play the "long" game. Studies in the 60's showed omega 6 content in human fat stores as low single digit percents--more recent studies show it going as high as 30 percent in some modern populations. There's the effect of your last meal--and then there's the effect of your own fat stores.

The endocannabinoid thing--there's a line of research in mice connecting "overeating" with endocannabinoid production from omega 6 linoleic acid. At 8 percent linoleic acid, anywhere from low to high fat, the animals eat to get fat. At 1 percent linoleic acid they remain lean--the supposedly fattening effect of the high fat diet disappears. No idea how/if this translates to humans but... on the standard diet, roughly half the fat we oxidize in a day comes from fat stores, half from diet. Somebody eating no omega 6 fatty acids at all, but with 30 percent omega 6 linoleic acid in their fat stores, if they were to release their fat in the same ratio in which it's stored, could still be working from a pretty high omega 6 level. And of course calories from fat stores would go up on a calorie restricted diet.

The endocannabinoid "bottleneck" is production of arachidonic acid from the linoleic--also a potential bottleneck for inflammatory eicosanoid production. Omega 3 fatty acids either downregulate production of arachidonic acid (enzymes that produce dha also produce arachidonic acid) or in the case of alpha linolenic acid, compete for the enzymes that produce both arachidonic acid and dha, epa etc.
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