By Christian Wernstedt
Two short notes on subjects that I've been thinking about lately.
Some evidence point to the fat palmitic acid as the type of saturated fat that one might want to avoid over-eating rather than saturated fats in general. Palmitic acid has been shown on a mechanistic level to make scavenger macrophages gulp up oxidized LDL which is believed to be an important step in the process of atherosclerosis.
Another issue with palmitic acid is its role in leptin- and (temporary, "physiologic") insulin resistance.
Somewhat as a confounding data point, I can report that my own brief experiment with consuming a large amount of heavy cream and butter for a couple of months before a blood test, and then dropping the extra saturated fat and do a comparative test after a month revealed a higher total cholesterol number on the diet high in saturated fat, however with a corresponding rise in HDL, while triglycerides stayed constant. (The informal experiment probably also led to a significant shift in total calories between the two "diets" which could have impacted the result.)
In terms of looking at formal risk metrics such as the ratio between HDL and triglycerides and HDL to total cholesterol, the cream and butter diet was a notch better than the diet without those items. (Though again, there may be confounding factors such as calories and the fact that adaptations to a specific regimen can take much longer than a month.)
I think the jury is still out on this, but the idea proposed by Cordain that modern grain fed animals have a higher proportion of palmitic acid in their meat than the animals consumed during the paleolithic provides a further clue to the effect that we might not be well adapted to "modern" levels of palmitic acid. This would of course include the palmitic acid that is released from the liver when we overeat carbs!
I sometimes feel that my heart rate is inexplicably high at times during the day, and if I just get the slightest stressed, the rate can sky-rocket. (I can feel the veins in my neck just pound like crazy.) I also suspect that I have a lack of really great blood sugar control, despite eating a low carb paleo diet.
I have come to suspect that coffee is one of the culprits in these problems (under-eating may be another). A weird thing with coffee for me is that it has some sort of delayed action, such that it can cause an explosion in adrenaline (and cortisol?) release hours after I've actually consumed the coffee.
I'm therefore experimenting with reducing my coffee intake so that I would only drink enough caffeinated coffee such that I precisely avoid withdrawal symptoms. This sometimes means that I drink just half of a cup of espresso and then I throw away the rest. I may do this two times a day.
So far I'm quite pleased with the results. Subjectively I experience a calmer mood and less of those undue fight-or-flight moments.