Friday, November 24, 2017

Paleolithic Principle and Diet

This is an explanation of the Paleolithic Principle and my expectations of the Paleolithic diet.

First off we should get rid of the myth that Paleolithic people led short brutish lives. This statement is a general misunderstanding of the concept of life expectancy at birth and due to the bones found of paleolithic people.

Paleolithic people generally had much better bones than the neolithic and present people. A life expectancy of 30 does not mean that people lived only till 30 years. This means that average of the age at death of people was 30 years. Lots of children died within a couple of years after birth, which reduced at higher ages, but still significant number of children did not live past 15 years of age. After that death due to diseases and accidents reduces significantly. It is common to find men/women of age 80 years in hunter gatherers.

Also menopause which starts after 45 years cannot evolve unless people are living beyond the age of 50 regularly. It is an adaptation to reduce resource competition by taking females out of the task of producing offsprings thereby reducing the population, and provide help to the younger females so that the young ones can be cared for better.

There are two phases in human development. Before migration from Africa, and after. The adaptation made before the migration are common to all humans. Adaptations made after are not.

It is easy to recognize that humans migrated from Africa because the genetic variation in Africa are much more than elsewhere. Also the reason why humans have the huge number of sweat glands and very little hairs. This is because humans evolved in a hot and dry environment.

The diet prior to migration would be called the paleolithic diet. The later changes are due to adoption of agriculture. Where humans started to grow grains and legumes and drying and storing them for lean periods. This period is marked by higher consumption of grains and legumes and adaptations based on these.

There are controversies regarding Paleolithic diet. Paleolithic period human remains obtained are high in 15N Nitrogen isotope. Since these are high in grasses rather than other types of plant food, and humans cannot consume grasses, it was assumed that humans ate a lot of meat of animals that were eating grasses. But recently it has been discovered that there are some tubers that are high in 15N, particularly the tiger nut. It is possible and makes more sense that humans consumed these type of tubers as a majority of their diets. In fact some of the old African tribes use these as their staple. 

Hunts are not always successful, and there are very few extinctions in Africa, so it is likely that humans evolved and became adept at hunting, while animals evolved in Africa to avoid getting hunted. When skilled humans moved out of Africa, they were a totally different beasts for the animals in the rest of the world and the animals could not adapt and were extincted.

So humans must not have obtained a regular supply of meat. Also fruits in Africa are huge. It is very much obvious that humans obtained a large part of their calories from high carb foods.

We also know that Africans have a much longer colon, which means that humans had a much higher consumption of fiber. The fruits and tuber consumption would provide them with the high fiber content.

There is another observation. There is a bird called honeyguide. It has evolved along with humans and can guide them to beehives. The present African tribes use the Honeyguides to obtain a lot of honey during season. This results in a very high sugar diet during the season. The tribals do not suffer any harmful effects of this high sugar diet.

Hunts succeeded rarely, so meat was not a big part of the diet, but smaller animals could be caught regularly. So it was a regular part of the diet, but not a staple.

Fat is very difficult to obtain in the wild. Most of the plant foods don't have much of it. And animals in the wild don't accumulate much fat except during specific seasons or pregnancy. Many tribesmen try to avoid killing females, and particularly pregnant or mothers. This can be seen in meat preferences to this day.

Humans have been cooking for at least a couple of hundred thousand years.

Tribal people are not particularly known for their cleanliness. And this means that they get a huge amount of bacteria in their bodies.

To summarize paleolithic diet was based on real and whole food.
It was high in carbs, fibers and simple sugars.
It contained regular meat consumption but was not a major part of calories.
It was low in fat.
Majority of calories came from tubers, followed by fruits, and seasonally honey.
Grains were very rare and legumes were never dried. Legumes were part of vegetables.

Now the paleolithic diet ideas cannot be directly used in modern times.

It is difficult to get good quality honey for most people. Refined foods must be avoided including refined sugar. Raw cane sugar maybe ok, in small quantities.

Our digestive system can no longer handle huge amounts of fiber. Still its a good idea to determine how much fiber we can handle, and aim for that.

Meat and other animal products are good to consume regularly.

Grains and dried legumes should be reduced in the diet. Dried legumes are probably ok after sprouting.

Wednesday, May 31, 2017

Weight loss theory and strategies

Weight loss requires calorie deficit. That is the thermodynamic principal.

Now this can be done via two ways, reducing intake and/or increasing expenditure. The better option is to use both together in various ways.

Both have their difficulties and pitfalls. And as you will realize below, you cannot have a sustainable weight loss without using both together.

Before we begin the most important part to understand is that the body has a fat set point, which it will defend. To force the body to lose weight you have to change your diet/exercise regime. And to have sustainable weight loss you have to have a sustainable strategy.

Lets take the less complex part, increasing expenditure. This will have a feedback in increasing hunger, which causes more intake, due to the fat set point. Also there is the case of adequate rest, and avoiding repetitive stress injuries. You also want to avoid overusing very few muscles. The exercise needs to be overall body, with adequate rest, and a healthy diet.

Now for reducing intake. This can be done two ways.

Destroy your digestive system so that it cannot absorb the energy. For some reason bariatric surgeons favor this route, possibly because it makes them more money. You can also have it destroyed by overusing antibiotics.

The other more prudent way is to eat less. This strategy is pretty complex because of several reasons.

First the body has a set point which it wants to defend. So attempting to eat less will increase your hunger and temptation to food. The strategy of fighting your basic hunger will be a failing strategy. So your strategy has to reduce your calories but while achieving satiation.

Second the body can control its expenditure, by releasing or holding body heat. Basically the body needs to burn calories for doing work as well as maintaining body heat. So it can reduce the expenditure by slowing metabolism by reducing body temperature. This is the starvation response, the thyroid hormones are down regulated and metabolic rate is reduced. This happens when the calorie intake is low too for too long.

Third the diet must provide enough micro-nutrients for the body's upkeep. Your body can supply the energy by burning the excess fat, but it has limited stores of micro-nutrients. So these must be part of your diet in adequate amounts. This actually implies that the diet should be low in carbs and fats, as both are plain calories which you want to reduce. It is best to consume whole natural foods.

Fourth the diet must be highly satiating. This is the most complex and subjective part of the diet. It depends on every persons personal tastes and gut flora. There are a few generic ideas that would help.

Protein is more exothermic so keeps your metabolic rate higher, and is not readily used for energy, which makes it more satiating. Strive for protein intake between 15%-30%. The exothermic part of protein limits its intake during tropical summers. In extreme winters protein intake can get a lot higher and will be helpful to deal with winters. The body on an average has the ability to digest 250 gms of protein, which depends on the excretion of nitrogen from the body.

Fibers are more filling and good for the gut flora. The ability to digest fiber depends on the gut flora and the type of fiber. Generally you want a good mix. Normal humans can absorb 100gms per day, but you need to have adequate gut flora for it. It might take some time to build enough gut flora.

There are some foods which are highly satiating. The foremost example is the potato. The potato hack is the fastest way of losing fat. It is difficult to consume more than 1200kcal from boiled and lightly seasoned potatoes, if no fat or other caloric additives are added.

Lastly there is fasting. There are several fasting protocols which are used. The best seems to be eating in a small window. For example 16 hour fasting and 8 hour eating window. Another variation is fast5, which is a 5 hour eating window. Some people also do alternate day eating. The fasting protocol does not limit calories within the eating window, so you are never under eating for too long. It is generally good to sleep on a more or less empty stomach. ie Almost never have a big dinner.