Nicolas said:
I have ordered their book and should receive it in a few days. Looking forward to reading it.
Me too! I've also ordered "Primal Body, Primal Mind," another one where the author, Nora T Gedgaudas, has combed through the peer reviewed scientific literature to present the benefits of primal diets and the detrimental effects of the modern Western diet.
I've got another one on the way called "Ketogenic Diet" by Lyle McDonald. He's self published, so I had to order it directly from his site. I think he comes at it more from a body building perspective, which doesn't really interest me, but apparently he's quite meticulous about gathering evidence.
I've bought all of these books in the hope of allaying this nagging cognitive dissonance I've had about the low carb thing. In reading a lot of the low carb blog stuff out there (I read a lot of this stuff), there seems to be a fairly sizable number of people who fail on it. They do great for awhile, but after some time on the diet, usually a few years, their health starts to fail. A lot of their stories read the same as vegans who failed on their diets and had to go back to meat.
For a lot of these people, it seems their thyroid starts to crap out, leading to tiredness, coldness, digestive issues (particularly GERD, heartburn), hair loss, and a number of other hypothyroid issues. These issues seem to return to normal once they add carbs back in.
Here's the latest one I've come across - http://www.cutthecarb.com/goodbye-cutthecarb/
180degree.blogspot.com is basically dedicated to low carb (and low calorie) recovery, where the writer and many of his followers have whole hog rejected low carb and taken on a diet with huge amounts of carbohydrate while maintaining low blood sugar levels and glowing health. It's not really difficult to imagine since this is what Weston A. Price found when studying primitive cultures - some cultures were eating diets with large quantities of carbs and were essentially disease free. It's obvious that humans can do quite well on a whole variety of macronutrient ratios without getting diseased or fat, but this doesn't mean these diets are the ideal, particularly when we bring in less mainstream ideas, like DNA changes.
So to be clear, I'm not bringing this up to be a naysayer. I honestly do believe low carb makes a lot of sense and could very well be the best diet for the human race. But obviously there are some people out there doing something very wrong and it's really biting them in the rear end. It may not be as simple as dropping carbs, end of story. I'm hoping that some of these books I've ordered will give me some hints on why this kind of thing happens to some people. I think it's important for us to make sure we're doing this right and avoiding the pitfalls that others have evidently fallen into.
So far, I've got a couple of hints. Apparently cortisol levels rise when on a low carb diet. There's some disagreement as to whether this is temporary, only during transition, or continues as long as you're restricting carbohydrate. Anyway, raised cortisol levels have a negative effect on the thyroid. This could be a possible pathway, so perhaps there's something we can do to keep cortisol levels low (oh, I dunno, maybe... EE? :D )
Another possibility is fungus. According to Paul Jaminet (he wrote a book called 'The Perfect Health Diet', which sounds like it's pretty close to what we do here, although he cautions against zero carb) http://perfecthealthdiet.com/?p=1032 while bacteria love sugar, fungus functions really well on ketones. People in ketosis who have fungus in the bloodstream could therefore end up with a pretty big issue and could lead to a number of symptoms. Chronic infection is another thing Jaminet mentions can be exacerbated by low carb.
There are other possibilities, of course. Maybe some of these people are still eating evil foods of some kind; not carbs necessarily, but something that's wearing on the system in some way. Dairy is fairly common in paleo circles, so this could be the culprit. Or they might not be doing enough fat. Or enough protein (remember that protein is need for gluconeogenesis to feed some of the brain and nervous system. Apparently the brain can only run on 70% ketones and needs the other 30% as glucose. Jaminet recommend 600 calories per day from protein and carbs combined [about 150g in any combination] just to make sure you're getting enough glucose for the brain while staying in ketosis).
The other possibility is macronutrient deficiencies, like sodium, potassium, magnesium, vitamin C, etc. Selenium and iodine are needed for the thyroid. Jaminet says copper or iron deficiencies can lead to hypothyroid symptoms because iron is needed for the liver to convert T4 into T3 (thyroid hormone) and low copper levels reduce tissue concentrations of iron.
Anyway, this ended up being a longer post than I intended. It's just where my head is at at the moment - I'd really like to get to the bottom of this. With all this research, I'm hoping all of this will develop into a SOTT or DCM article about ketosis when I've sorted through it all.