The fine folks at the Perfect Health Diet are proposing that we need to start looking for evidence of carbohydrate deficiency. They state that humans are likely the only animal this would effect due to the unlikely combination of a large brain and a relatively small liver. What are your thoughts? Or maybe more aptly, why do you disagree?
I'm skeptical. My auto-immune gut disease got better on zero carb, and I get sick less, which is exactly the opposite result predicted by their hypothesis. Which in itself seems somewhat absurd - deficiencies are real, measurable things with definite symptoms. If you eat zero fat, you'll get EFA deficiencies that will eventually kill you. If you eat zero protein, your body will be unable to accomplish a zillion tasks and you will die. If you eat zero carb... your lifelong autoimmune problems will clear up and you'll be healthy with no obvious deficiency?
Maybe zero-carb is suboptimal in the long term, but calling suboptimal a deficiency is abusing the term deficiency. You get real symptoms and real problems with deficiencies, not long-term survival with no obvious problems (ie Inuit).
You have only to follow Lex Rooker's n=1 4 year on going experiment in eating only grass fed meat and fat. His Dexa bone scans, his blood lipids, blood glucose are all excellent. He is truly zero carb and the meat and fat he eats daily...once a day comprises about 75% fat and 25% protein...and is eaten raw. About 2 pounds a day eaten at 2pm. No supplements. Lex does not consider eating a recreational sport...or a satisfying activity. He only eats to survive...not to seek pleasure.
Read his odyssey: http://www.rawpaleoforum.com/journals/lex's-journal/ 124 pages going from June 2008 to present.
The moral: There are no essential carbohydrates. Humans can live perfectly normal lives on meat and fat only....just as our ancesters did.
I am not closed to the idea that for some people, very low carb may be suboptimal or perhaps even make it to a point of deficiency. Some people may not be well designed for large amounts of gluconeogenesis. Or perhaps a lifetime of poor eating, toxins, poor nutrition in the womb, etc may have made them thus. A sick animal will not always do best on the same diet as a robust healthy animal. If you look around at how many pills the average person takes, most of us are in the 'sick animal' category. Certainly, I have heard some people say they felt like crap on very low carb but much better on say 70 to 100 grams carb per day. I would say 'feeling like crap' counts as a possible sign of deficiency or ill adaptation of some kind. I am more inclined to call it an illadaptation though. "Deficiency" makes it sound like it will hold for the general population but seems like at least half the population (that tries it) feels very good on very low carb. I also think that we should first make sure that people are not deficient in other nutrients before assuming the prob is carbs themselves. Maybe the prob for some people is actually related to other nutrients that often co occur with carbs.Kinda goes with the 'islands of safety idea.' It might be fine to go very low carb as long as certain other criteria are met at the same time, but since we don't know the criteria, then it will be somewhat left up to chance if your lifestyle will meet those criteria or not.
I am looking forward to the rest of the series. Until they make their case, it's kinda hard to judge it. The book did include some information on this, but not a ton. I would definitely recommend the book though, it is the best nutrition book I have read so far.
This is a fair question. Loren Cordain notes (as does the article) the extreme rarity of low-carb diets among hunter gatherer peoples studied, the Inuit being the most noted exception. While it is telling that there are humans who can live on very low carbohydrates we can't dismiss new observations about how quickly evolution can occur. There are some who advocate eating no less than 400 calories in the form of carbohydrates in the long term (sorry, I can't find the reference). Even so, Cordain shows that most studied hunter gatherers get around 50% of their calories from carbohydrates of various forms.
Of course, these are hunter gatherers being studied in the 20th Century and not pristine cultures. Who knows how they ate before the clash of empires destroyed lands and monopolized resources. Its hard to speculate on exact numbers. What is easier to observe is that we definitely ate more fat than the current Federal recommendations and we didn't eat any HFCS or transfats. As Dr. Lustig notes the problem may just be overconsumption of fructose.
The Inuit are not zero carb people. Even putting aside their consumption of berries and sea vegetables, the staples of their diet (raw organs) have small amounts of carbs and are more nutritious in certain vitamins like Vitamin C. They don't eat a lot of muscle meat like many of these zero carbers do. Their whole diet is built around approximating a nutritious human diet given what they have in a harsh cold climate. They've done the best they could to avoid deficiency diseases like scurvy using animal sources. They eat lots of fat only because the animals that are common there have lots of fat naturally, and it helps to balance out protein in the absence of carbs.
In the absence of supplementation, a truly zero carb diet will lead to scurvy and perhaps other deficiencies. Low carb dieters do not even have to eat fruit to get Vitamin C, in fact parsley is a good source but it has a small amount of carbs. But if you are trying to avoid all carbs you are limiting what you can eat even from the animal.
Thanks Andrew. I'm looking forward to our continued conversation about this. I guess I'll get it started with a few thoughts.
This was the "oh, there it is" moment for me:
Some micronutrients are required for mucin production – notably vitamin D. [7, 8] Poland is fairly far north, and many of the Optimal Dieters could have been low in vitamin D.
Considering some of the explanations we were able to make with the China Study diet and a number of other places where vitamin D pops up, I think this is very important. Note that Eva said something like this already, below: "I also think that we should first make sure that people are not deficient in other nutrients before assuming the prob is carbs themselves. Maybe the prob for some people is actually related to other nutrients that often co occur with carbs." Good call, Eva. We should also give some credit to the Perfect Health Diet folks for their skepticism. By the way they make a similar point about iodine.
Another important thing I think is that they advocate getting at least 30% of your calories (well, they say 600 calories for a 2,000 calorie diet) from protein + carbohydrate. The idea is that even if you don't have any glucose (i.e., if you do it 600 protein calories and 0 carbohydrate calories) then you'll still have enough protein for manufacturing ketones and glycogen to keep everything running. But at the end of the article, after having talked about cancer risks, they write:
It’s plausible that a zero-carb diet that included at least 600 calories per day protein for gluconeogenesis would not elevate gastrointestinal cancer risks as much as the Optimal Diet. But why be the guinea pig who tests this idea? Your body needs some glucose, and it’s surely less stressful on the body to supply some glucose, rather than forcing the body to manufacture glucose from protein.
But isn't that really the million-dollar question? Just how "stressful" is it for the body to manufacture glucose from protein?
Anyhow, all this aside, I have to say there is something intuitively appealing about paying attention to your body to see if you have dry eyes or mouth. I've felt this before, and I know it goes away with a little carbohydrate. Although in my case it really is just a little -- much less than they are talking about. OK, looking forward to other people's ideas.
Starchy vs Non-Starchy Vegetables 2 Answers