If you are not making waves with at least some controversial proclamations, you're probably not making a very big impact either.
In Stephan's article from today, he addresses 3 additional questions that he did not get to address on the Chris Kresser Podcast. He discusses a few topics that have brought some fiery comments from his readers.
He made quite the controversial statements about carbohydrates... two in particular:
"I think that an optimal diet for lean healthy people is probably not restricted in macronutrients, and if anything a diet biased toward carbohydrate is better for overall long-term health than one biased toward fat."
and in the comments, he said:
"However, I think most of our ancestors have probably been eating more carb than fat for a very long time, so my default stance at this point is that if you're going to bias your diet toward a macronutrient, I'd go for carb."
Also, regarding insulin:
"Foods that spike insulin the most in humans lead to the greatest satiety and lowest food intake at subsequent meals".
In a nutshell, Stephan said...
1. a carb based diet is probably healthier than a fat based diet.
2. our ancestors ate more carb than fat for a long time, so high carb is probably better than high fat.
3. eating foods that spike insulin the most is a good thing.
1 and 2 are very similar, just said in a different way, but all 3 points certainly challenge much of what I've come to understand after going Paleo.
Do you agree or disagree with these statements from Stephan?
Update May 18, 2011: Stephan has added a follow up post in response to some of the outcrys...
My 2 cents-
Whole Health Source, along with PaNu/Archevore and Hyperlipid, has been one of my primary sources of information as I have made my personal diet transformation. Specific to WHS, I recently read every one of Dr Guyenet's posts from start to finish including the comments. I don't throw around compliments lightly, but he is definitely a very intelligent and thoughtful scientist that is able to synthesize recondite and abstruse research results, and present the information in a manner that is accessible to people that are not as technically versed as him.
I have not observed that he makes bold proclamations without having done a substantial amount of research in advance. He has earned my trust. Note this is NOT synonymous with saying I take EVERYTHING he writes as gospel. He also openly acknowledges the uncertainty of some things while other "gurus" implicitly assert their omniscience. I respect this.
In having read all of his posts, there have been many examples where he had multi-part series and left readers (intentionally?) hanging for the next post. Eventually he has always seemed to tie things together. I, for one, will give him the benefit of the doubt that he will do so with the current series on Food Reward. We will see.
The series on Food Reward has the word "dominant" in the title. Not SINGULAR, EXCLUSIVE, ONLY, SOLE, but dominant. Maybe I am misreading the feedback to his posts, but some people seem to have overlooked the inclusion of DOMINANT. Some people, particularly extremists in our community, seem to not only struggle with the multi-variate nature of nutrition, but even more so the prospect that Paleo 2.0+ might challenge the alleged undeniable truths of Paleo 1.0.
I certainly have my questions based on the initial parts of the series, but I intend to let him fully elaborate his position before judging it. Whether I ultimately agree and/or whether it influences my future diet is TBD. Regardless, I eagerly await his next post(s).
I don't have real problems with 1 & 2. It's been shown that humans evolved eating a variety of diets. The diseases of civilization engulfing us today have less to do with macronutrient ratios than food toxins (wheat, gluten, casein, refined sugar, refined/pulverized flour). These food toxins all happen to be carbs. That does not mean all carbs are bad. That's what some people seem to miss.
Now, if you have diabetes, you may need to give up safe starches (rice, potatoes, sweet potatoes, yams, cassava, turnips, etc.). That's probably obvious.
But it's pretty clear that those tribes that subsited on carb-heavy tuber or even rice diets never contracted diabetes. It was the onslaught of refined sugar/fructose and white flour which is wreaking havoc.
It's also easy to imagine that most tribes ate a carb-heavy diet. It's simply not that easy to subsist on a carnivorous diet. You have tubers that are simply too easy to pass by. Hunting does not always lead to a successful catch. You can go days witout a catch. Also, you couldn't really store your catch.
Now for #3: Perhaps he means potatoes and yams induce initial satiety (they do). I don't think though they cause you to eat less at subsequent meals. They seem to whet your appetite for more food, starch or otherwise.
I love Stephan's comment, and see criticism of it as a microcosm of a major paleo problem. That problem is "taking your experience and view of the literature as paleo gospel".
Here are some things that have been mentioned as fact around paleohacks in the past few months:
And here are things that have been largely ignored:
I have no doubt that Stephan will explain more in later posts. It is one thing to talk about how we can eat no carbs and live, or study Inuit. It is another thing to wade through reading about long term ketogenic diets. Eating a diet consisting of tons of meat every single day, supplemented with extra fat, should not necessarily be considered the automatic winner among best human diets. Note that Stephan does not generalize this at all to medical conditions (e.g. diabetes), and is more careful about making definitive statements than many on paleohacks.
I wasn't even going to comment, but what I have seen here so far is the failure to perceive Stephen's statements for what they really are; "Emperor's New Clothes" i.e. statements riding mostly naked. There may be explanations in the future from Stephan that might dress up and explain the statements, but currently there are none.
Our ancient ancestors likely did not eat significant digestible carbohydrates, as the increasing size of our brain and its concurrent metabolically expensive energy expenditure could not likely have evolved on a high carbohydrate diet. The so-called “Expensive Tissue Hypothesis” that is quite famous and popular in paleoanthropology and likely would have already been discussed in this and other paleo blogs previously, describes this. For those unfamiliar, the citation and abstract is below. However, the belief in this "hypothesis" and even what our ancestors ate are moot points anyway. What our ancestors ate is irrelevant for longevity and post-reproductive lifespan. Diets evolved for reproductive success. I have discussed this recently in prior posts.
Whereas I commend Stephen for putting the major onus of obesity and health onto leptin, it appears that he is making a couple of basic mistakes regarding hormone signaling in general, especially pertinent to insulin and leptin. When endogenous hormones such as insulin and leptin do their job, they will keep you healthy. However, it is not the size of a signal that is relevant, but the accuracy of what's "heard". Metabolic diseases, and in fact all diseases, are secondary to miscommunication. The problem with insulin and leptin is not insulin and leptin per se, but insulin and leptin resistance when they cannot get their messages properly heard. The body, and in particular the brain, then responds to high insulin and leptin as if they were low. Stephen seems to miss this in his current post, and more importantly the cause(es) of this. I firmly believe that the major cause of both insulin and leptin resistance is repeated spikes in both of those hormones secondary to spikes in blood glucose, so where there might arguably be a short-term benefit from a spike in insulin and leptin, long-term spikes lead to a reduction in signaling, and more importantly a corruption in the where, when, and how the signal is being received by different organs and cell types.
Also ignored in the post is the copious amount of research over the last 15 years linking elevations/spikes in insulin and glucose with accelerated aging.
The Expensive-Tissue Hypothesis: The Brain and the Digestive System in Human and Primate Evolution Author(s): Leslie C. Aiello and Peter Wheeler Current Anthropology, Vol. 36, No. 2 (Apr., 1995), pp. 199-221
Brain tissue is metabolically expensive, but there is no significant correlation between relative basal metabolic rate and relative brain size in humans and other encephalized mammals. The expensive-tissue hypothesis suggests that the metabolic requirements of relatively large brains are offset by a corresponding reduction of the gut. The splanchnic organs (liver and gastro- intestinal tract) are as metabolically expensive as brains, and the gut is the only one of the metabolically expensive organs in the human body that is markedly small in relation to body size. Gut size is highly correlated with diet, and relatively small guts are compatible only with high-quality, easy-to-digest food. The often-cited relationship between diet and relative brain size is more properly viewed as a relationship between relative brain size and relative gut size, the latter being determined by dietary quality. No matter what is selecting for relatively large brains in humans and other primates, they cannot be achieved without a shift to a high-quality diet unless there is a rise in the metabolic rate. Therefore the incorporation of increasingly greater amounts of animal products into the diet was essential in the evolution of the large human brain.
When I ate a high carbohydrate diet (non-calorie-restricted), I felt consistently horrible and could not shake a pound of weight. With a high fat diet, I feel great and the weight is slipping off. I think that is evidence enough for me. The only other way I have lost weight was with a calorie-restricted diet incorporating all foods. Though, I was consistently hungry and had to force myself not to eat. I have not encountered any of those problems eating the paleo way. More people need to rely less on so-called scientists and experts and just do what feels right.
When a well accepted idea is rebutted by someone considered to be a supporter of this idea, people tend to be confused/annoyed. Specially if this person is considered as a guru or an expert on the subject. This is more obvious in the paleo world. As far as I rememember, Stephan never said and/or stated that low carbohydrate is the only way to go. And by the way, I consider Stephan the most knowledgable guy regarding obesity.
This means that I agree with Stephan regarding high carbohydrate diets? No. This means that his apparently "new" ideas are going to change totally my diet and/or view on nutrition? No. What Stephan is saying is that HIS opinion, based on HIS research, is that a carbohydrate oriented diet is better than a fat oriented diet. People need to understand that humans are metabolically very flexible. We are adapted to survive on different types of diets. Everyone will have their own opinion about the perfect diet, but there are only a few people that are 100% convinced that their approach is the way to go. So when someone respected challenges their ideas, they shiver. This happens when you are not completely sure about your ideas and/or dont understand them in the first place. We must have a holistic approach to nutrition. This coming from a huge proponent of ketogenic diets who does not have a problem when someone supports a high carb diet with valid arguments.
I think that "carbohydrate" is the "saturated fat" of the paleo world.
What people miss is that when you switch to a low carb diet, you neccessarily switch to a low sugar, low trans fat/veg oil and low boxed junk food diet.
I went low carb and felt tons better initially. Looking back, it was obviously because I suddenly stopped eating around half or more of my calories in soda, chips, sweetened cereal, candy, cookies, muffins and sweetened yogurt every day.
A few months of high fat/low carb paleo also gave me: muscle loss, fat gain, slow healing, rough/dry hair and skin, insatiable hunger, insanely high cholesterol and hypothyroidism.
To add one more opinion here.... I think that we all like to geek out on foods, macronutrient ratios, insulin, etc. That's why we come onto this site. However, a variety of diets have been shown (eskimos vs. kitavans) to be healthy and allow a generally disease-free life.
Food quality seems to take precedence over everything else, and by that I mean avoiding processed foods and especially sugar, which we can all agree to be detrimental.
I was quite shocked to read his post, however if we're honest (and currently healthy) I don't think it matters what you eat as long as it's real food.
With three points it's difficult to only agree or disagree with him. I'd say points one and two are not wrong. Point three is dependent upon the individual. Some peoe find great satiety from foods that also happen to have large insulin responses. But the big thing many people forget is that THAT'S FINE IF YOUR HEALTHY. I eat white or sweet potatoes with every meal. My insulin probably goes up from that. But that's fine, I'm fit and active. Insulin is in our bodies exactly for that reason!
For point one, again if you're lean and healthy a carb-heavy diet is great! I'm on it, most anyone who is interested in athletic performance is on one. That does not mean grains, it just means carbohydrate. Tubers.
For point two maybe he means our ancestors of more recent generations. Yes during ice ages etc maybe fat and protein were the leaders but I'm sure for 50, 60 thousand or so years tubers have played a huge role. Perhaps outweighing fat. The fat attached to meat yes of course was always eaten but that's it. No olive oils, no macadamia nut oils, no coconut oils. So perhaps carbohydrate played a larger role for a longer time than many pale eaters think.
personally I'll let the numbers speak for theirselves. I know countless people that have lost much weight and felt wonderful doing paleo, that by itself should prove its effectiveness.