Regarding fats and Coronary heart Disease and fats and paleolithic nutrition, there are a few points to be made:

First, on the molecular level, some saturated fatty acids (lauric, myristic, and palmitic acids) decrease LDL receptor activity and increase LDL production.

I think that this evidence can’t be ignored, as the evidence that most mammals and hunter-gatherer populations have low total cholesterol.

Nevertheless, when it comes to estimating the intake of saturated fatty acids in the paleolithic era, one has to rely on the animals that still exist, and the data shows that fatty acid composition of wild animal’s fat is different from domestic animals.

For instance, in wild animals (and I think Dr. Cordain has new information to be released on that) most of the fat in marrow is monounsaturated, which explains why he recommends olive oil (70-80% of it is monounsaturated) to emulate that fatty acid profile (most people, including me, aren’t willing to eat marrow, as most people aren’t willing to eat brain to get their DHA, and rather prefer to eat fatty fish or to take a fish oil supplement)

In his website, he says: “There is absolutely no doubt that hunter-gatherers favored the fattiest part of the animals they hunted and killed. As far back as 2.5 million years there is incredible fossil evidence from Africa showing this scenario to be true.”

So, it is true that hunter-gatherers preferred the fatty portion of the animal, but most of the fat was monounsaturated and half the saturated fat they ate was stearic acid, which has a neutral effect on LDL.
In my opinion, since it is very hard (at least in Europe)to get wild game, and most people aren’t willing to eat the fat and the organs of wild animals, a second choice would be lean animal protein, along with coconut oil and olive oil.

Bottom line: I don’t think that increasing saturated fat in a very low carb diet will cause any harm, but I’m just not certain of it, and it appears that monounsaturated fat was the main fat consumed by our paleolithic ancestors. There is an interview with DR. Cordain, where he briefly discusses this with DR. Richard Feinman, and where Dr.Feinman talks about a recent study regarding low carb diets and metabolism of saturated fats - you can get it on http://lavida.kgnu.net/lavidaradioshow.php?show_id=331

It seems that under a low carb diet, things work in a different manner. In a recent study (Forsythe CE, Phinney SD, Fernandez ML, et al. Comparison of low fat and low carbohydrate diets on circulating Fatty Acid composition and markers of inflammation. Lipids. 2008 Jan;43(1):65-77) comparing low carb and low fat diets, it was shown, that despite the three-fold greater saturated fat in the diet for the low carb group, saturated fat in the blood turned out to be higher in the low fat group, so maybe if you eat a low carb diet, a high saturated fat intake won’t harm you, but under the typical american high carb diet, I think that it will harm you, because it downregulates the LDL receptor.

Regarding butter, I question its safety, not because of the fat that it contains, but because the milk that we are now consuming is quite different from what more primitive people consume. Modern dairy cows are usually pregnant and continue to lactate during the latter half of pregnancy, when the concentration of estrogens in blood, and hence in milk, increases.

See:
Ganmaa D, Wang PY, Qin LQ, Hoshi K, Sato A. Is milk responsible for male reproductive disorders? Med Hypotheses. 2001 Oct;57(4):510-4.

Ganmaa D, Sato A. The possible role of female sex hormones in milk from pregnant cows in the development of breast, ovarian and corpus uteri cancers. Med Hypotheses. 2005;65(6):1028-37.

I think coconut milk would be a better choice.

But when it comes to fats and cardiovascular disease, we know that trans fat are a much bigger danger. Trans fat increases the catabolism of apo A-I and decreases the catabolism of apo B-100, which results in low HDL and high LDL.

Besides, trans fat increase inflammation, concentrations of lipoprotein(a) and triglycerides, insulin resistance and cancer risk.

Polyunsaturated lipid has no effect on LDL production but increases LDL receptor activity, so they are promoted as healthy fats. Nevertheless, an Omega 6/Omega 3 ratio above 4/1 increases the risk for many diseases (funny that you could have figured out this, just by estimating the ratio of a Paleolithic type diet – 2/1 to 3/1). This is one possible explanation for the high rates of death from cardiovascular disease in India.

Another explanation are lectins, and if you check the two last newsletters From Dr. Cordain (http://www.thepaleodiet.com/newsletter/back_issues.shtml) , along with his paper on peanut oil, you’ll have a better explanation of this (I know that he is conducting a human experiment at CSU with peanut lectin and wheat lectin, and after it is finished, he will publish a paper exposing this theory in detail).

In a nutshell, and quoting him, “elevated LDL and VLDL cholesterol in the bloodstream are necessary to induce the early non-fatal atherosclerotic lesion (the fatty streak), and chronic inflammation is required to cause the progression of a fatty streak into a mature atherosclerotic plaque and the subsequent fatal rupture of the fibrous cap surrounding the plaque.” What causes inflammation? One of the dietary factors are lectins (but I suggest you read the newsletter, to understand this). This explains why the Masai, despite eating an enormous amount of saturated fat, and having extensive atherosclerosis, don’t die from it.

MC

This week, I cooked some ground, grass-fed beef with browned onions, garlic, tomato puree, nutritional yeast, and broccoli-kale (Italian kale that’s sprouting into flowers). It was delicious.

Food Is Love