Your theory of metabolic "atrophy" is interesting, but a more straightforward explanation of sugar addiction would be that the ingestion of concentrated forms of sugar (e.g. breads, pastries, candies) stimulates insulin production, which reduces the level of sugar in the blood, leading to symptoms of low blood sugar, which prompt the addict to eat more sugar. If my understanding is correct, insulin also promotes the storage of fat (see Philologic Effects of Insulin http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/pancreas/insulin_phys.html). Of all the published diets I'm aware of, the ones that make the most sense in metabolic terms are the various forms of the Paleo diet, and the South Beach Diet. The South Beach diet discourages grain consumption, but unlike the Paleo diet, it includes dairy products.

What do you mean by "bread".

There are many, many types of bread, no doubt having various glycemic indices. Has there ever been a comprehensive research program to measure this?

You are probably referring to the most common commercial "bread substitute" made from highly refined, denatured wheat flower, sugar, yeast, chemicals, etc.

But what about real sour dough breads made with organic stone ground grain such as wheat, spelt, rye, etc. Or, even better, sprouted grain Essene or Ezekiel breads?

A macrobiotic style diet, based on whole grains has been shown to be very effective and nourishing.

Great stuff !
The one point I would argue with is "My non-scientific advice is: don’t try to go cold turkey"

In my view breaking the sugar / starch addiction is about training your body to use body fat and ketones as power sources, and to train your mind in new habits of eating, actually a new perception of what is food and what is not food. Certainly in my case, in the first few weeks while I was establishing the new habits, I found it very powerful to say to myself and others "I don't eat sugar / starches", and refuse the bread / cake / pie / nachos /soda etc. Saying "I'm trying to cut down on sugar / starch" inevitably sets up "but, just for now" and there you are starting to undermine your new habits and revert to your old ones. Of course once the new habits are properly established going off-piste a little is no harm, as long as it is not so long extended as to form a new habit in itself, but frankly I look at a lot of what people around me eat and instead of thinking "I wish I could have some of that but my diet won't let me" my response is "Wow, you actually think that stuff on your plate is food ?".

My personal journey to Paleo was via Atkins, and Atkins induction is pretty much carb cold turkey. Whereas I agree Atkins was wrong on sugar-substitutes like sucralose (to me they reinforce the sugar habit) and he missed the seed-oils issues, he deserves massive credit for popularising low-carb in the face of vitriolic opposition.

Great article. A couple of minor quibbles, however. Regarding "...Paleolithic hunter-gatherers got perhaps 1/3 of their calories from carbohydrate," it should be noted that this depended on where those hunter-gatherers lived. My own ancestors, for example, had much less opportunity to find fruits, veggies, and tubers while following buffalo herds on the plains than did other societies that lived in more tropical climes.

Also, I don't think the ability for the body to attain ketosis and start burning fat reserves can really be said to have atrophied, it is just that this switch is almost never thrown anymore. Nowadays we can pretty much get any sort of food we want, all it takes is a trip to the local supermarket, so we never go into seasonal ketosis.

However, in Paleolithic society, everything except meat was seasonal. Hunter-gatherers would gorge themselves on sweet fruit, for example, when it was available. It was a good source of vitamins, and it was a good thing to go into winter with a little extra fat as insulation. But, once that source of carbohydrate was gone, it was gone, and ketosis set in, allowing our hunter-gatherers to emerge into spring lean and ready for the next big hunt, move to the spring camp, or whatever.

Our bodies evolved in such a way that they would fatten up for winter, and lean down for summer. In fact, for most of our history, we had little choice, assuming gathering was good. This, I think, is the reason we like sweets. It was for fruit, not candy. Fruit was good for us, in moderation, so it tasted good. But to many, if sweet is good, even sweeter is better.

Now, we no longer need to hunt, gather, or eat seasonally. So, we just keep eating whatever we think tastes good, and getting fatter.

Regarding cold turkey or not, I think it may depend on how much carbohydrate you were used to eating. As far as actual sugar goes, I was never allowed much as a child, and that carried over into my adult life. Once in a great while I would get a hankering for a candy bar or somesuch, but I literally only ate like two or three a year. The same goes for chips, and snacks in general. So for me it was pretty much a question of laying off the bread and potatoes. Cold turkey was not too difficult for me. It just meant more meat or more steamed veggies slathered in guilt-free real butter. Yum. 🙂

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