Saturday, 21 August 2010

Garden of Eden, Cain and Abel and paleo diet

Until recently I have not been aware of the discovery of Göbekli Tepe. It certainly is irrelevant if you are trying to figure out the proportions of micronutrients in the diet, but it helps to see the Civilisation in perspective, along with its dietary component.

In short, Göbekli Tepe is the oldest temple, built ca 12,000 years ago by hunters-gatherers in what is now south-western Turkey. Clearly agriculture was not a prerequisite for religion, architecture and complex social structure.

Here is the story of Göbekli Tepe, and here an even more thought provoking interpretation.

Interesting, that in one of the Sumerian myths one of the gods was supposed to offer Adapa (Adam) "bread of death", which was later adopted in the Genesis as fruit from the tree of life.

Wednesday, 18 August 2010

What fat you are you eating when losing weight?

Losing weight by losing fat has been compared to eating that very fat. Indeed mobilising adipose tissue storage releases quite a lot of saturated fat into the bloodstream. If nature invented this mechanism to allow seasonal fat storage and mobilisation, then this fat should not be bad. Or at least should not be bad seasonally, in moderation.

Neither palmitic acid does has to be bad, even if it produces transient glucose resistance. On the contrary, it may be precisely why it is good to facilitate glucose supply to the brain, as was argued by Peter @Hypelipid.

I am not assuming that palmitic acid is bad, but would like to know how much palmitic acid was eaten by H-Gs. This applies in particular to trigycerides with PA in sn-2 position.

It is quite possible that the amount of PA in human adipose tissue in HGs was more or less the same as the amount of PA in the animals they ate.

Human fat composition depends on diet. Here in Fig 2B you can see that the percentage of PA varies considerably between 15 and 22, though only sat fat in the diet was vairied. It can be expected that HGs consuming less carbohydates would have even less palmitic acid in their adipose tissue. Releasing that fat during the lean winter months would be more or less like eating fat from wild game.

Perhaps a little more palmitic acid is not harmful, or may even be more adaptive, but still it would be good to know the composition of adipose tissue in HGs.

Tuesday, 17 August 2010

Neolitic revolution to get a fix?

An interesting, if very controversial view on the origin of agriculture:

"Climatic change at the end of the last glacial period led to an increase in the size and concentration of patches of wild cereals in certain areas (Wright 1977). The large quantities of cereals newly available provided an incentive to try to make a meal of them. People who succeeded in eating sizeable amounts of cereal seeds discovered the rewarding properties of the exorphins contained in them. Processing methods such as grinding and cooking were developed to make cereals more edible. The more palatable they could be made, the more they were consumed, and the more important the exorphin reward became for more people.

At first, patches of wild cereals were protected and harvested. Later, land was cleared and seeds were planted and tended, to increase quantity and reliability of supply. Exorphins attracted people to settle around cereal patches, abandoning their nomadic lifestyle, and allowed them to display tolerance instead of aggression as population densities rose in these new conditions.

Though it was, we suggest, the presence of exorphins that caused cereals (and not an alternative already prevalent in the diet) to be the major early cultigens, this does not mean that cereals are 'just drugs'. They have been staples for thousands of years, and clearly have nutritional value. However, treating cereals as 'just food' leads to difficulties in explaining why anyone bothered to cultivate them. The fact that overall health declined when they were incorporated into the diet suggests that their rapid, almost total replacement of other foods was due more to chemical reward than to nutritional reasons."

A while ago I touched on exorphins as well.

But what if the fix from exophins helped us develop abstract thinking and mathematics? Did the !Kung know mathematics?

Which fat is fatter?

I have decided to pay more attention to fat, this time guilt-free. But I am still a bit biased against palmitic acid (16:0) and would rather go for other options.

There are three fatty acids in a triglyceride and I remember reading that position sn-2 is the most important, as fatty acids at sn-2 are most readily absorbed by humans. It appears that beef fat has the least 16:0 at sn-2: 11.6%, compared to 20.8% in lamb and 54.8% in pork. Here are the details in Table 3.

I also remember a study showing that different fatty acids abound in different cuts and that brisket was supposed to have the healthiest fatty acid profile. It was not clear if the analysis was done on a grass or grain fed animal. (BTW, grass is not natural feed for cows; their ancestors, aourochses, fed mostly on bushes and trees).

Fortunately the local organic farm sells brisket, which is otherwise had to get organic.

But the real good stuff is bone marrow and I am now searching for a source. Last time the butcher offered me a hip bone, rather than a marrow bone - the dog will enjoy this one as well. Problem is, I have no dog. Too embarassing to rectify.

Interestingly, the fatty acid composition depends not only on what animals eat, but on the temeperature. Studies showed that the Eskimos prefered the marrow from reindeer's smaller bones closer to the cold arctic ground (more unsaturated) to the more abundant marrow from large femur or humerus (more saturated).

Whoever comes up with a patent for cheap synthetic pure oleic acid production might hit the jackpot. The Chinese have already made some progress:

Monday, 16 August 2010

No turning back

It's been 9 months since I went Paleo and it seems to have been the right choice. I am symptom-free and full of energy. The only worry was cholesterol, which now looks as follows:

TC 252mg/dL
HDL 67mg/dL
LDL 172mg/dL (Friedwald, the Iranian formula would give 149mg/dL)
TG 68mg/dL

In addition, inflammation is close to zero:
CRP 3.73mg/L

And the only marker which may need attention is slightly elevated urea: 48.66mg/dL (uric acid close to upper limit: 6.4mg/dL, but higher level might be good for the brain :)

Did I cut down on saturated fat? No. In fact, I have been eating more animal fat and less olive oil and nuts. It seems that plant oils may be better for women. Men need testosterone and not plant sterols and 5-alpha reductase inhibitors which lower the level of dihydrotestosterone. Indeed, it is the latter which is responsible for masculinisation, while testosterone only helps the muscles grow. I have not seen the studies showing that olive oil or hazelnuts lower DHT, but have a gut feeling that it does in me. Plant oils should be ok in moderation, but if we are talking 200-250g of fat a day, you have to make a choice. Besides, even olive oil is loaded with omega-6.

And indeed, I have decided to eat less protein and more fat for a while. Grass-fed meat is almost impossible to get in the UK (may be grass-fed but grain finished), but lamb is probably the closest. There is a lot of organic meat, but mostly lean cuts. Besides, organic means fed organic grains. Good that the season for deer is starting.

I have experimented a bit more with cream (and ice cream), and I really like that stuff, but they do lead to muscus production and there is no way to get unpasteurised milk products here, so this will have to go. Besides, heat processed milk products mean oxidised cholesterol and lipids as well as AGE.

One more obervation: no tooth decay. Previously I had 1-3 fillings a year, now zero and no trace of tooth decay. BTW, I had stopped using toothpaste as well and have only been using thoothbrush and floss.

On the other hand, there was more calculus, so the dentist still made the money. Based on what I have read, more ammonia from dietary protein leads to more basic saliva which protects against dental caries, but facilitates mineral deposits. This has been reported by many Atkins followers. I suppose, cutting back on protein a bit should help me acheive the right balance between decay and calculus. Otherwise I will need to start chewing on raw bones to control calculus :)

Regarding weight, it is up by 2kg from 6 mothns ago, but the waist circumference is still the same. More muscle with moderate exercise 20min 4-5 days a week.

But I am still not 100% sure that I am doing everything right. I had been wrong with vegetarianism for so many years and I also thought I had read all the evidence (the China Study, he, he). But then again, at that time I could not read evidence critically, which now I can do. This is what I do for a living after all.