I'm very skeptical of reasoning like "it was like that in ancestral environment so it must be good". There are at least three reasons that makes me uncomfortable with the reasoning :
Even if we consider evolution to be a perfect optimizer (which it is not), there is a huge difference between "our digestion system is optimized to make the best possible use of food X" and "food X is best possible food for our digestion system". If you made an algorithm A optimized to transmit data on a noisy channel N, it doesn't mean the algorithm wouldn't run better on a less noisy channel C. There may be an algorithm B that work better on the clear channel C than A, but still, A can work better on C than on N.
Evolution doesn't optimize for the same purpose we do. Evolution doesn't optimize for us to live long, it has a very low pressure to make us live past ~60, for example.
We have completely different lifestyles and activities than we did during paleolithic. And the optimal diet very likely depends of lifestyle and activities.
That said, what would convince me to do a diet is not a plausible-sounding reasoning, but some evidence of short-term and long-term effects on a sane sample size, with a control group. Something which seems very rare in the diet field, saddly.
Your grounds for skepticism match the heuristic that Anders Sandberg and Nick Bostrom propose in The wisdom of nature quite closely. They propose this heuristic to evaluate interventions to enhance humans, but it's clear that it has much broader applicability. Here's the relevant excerpt:
...Suppose that we liken evolution to a surpassingly great engineer. (The limitations of this metaphor are part of what makes it useful for our purposes.) Using this metaphor, the EOC can be expressed as the question, ‘‘How could we realistically hope to improve on evolution’s work?’’ We propose that there are three main categories of possible answers, which can be summarized as follows:
• Changed tradeoffs. Evolution ‘‘designed’’ the system for operation in one type of environment, but now we wish to deploy it in a very different type of environment. It is not surprising, then, that we might be able to modify the system better to meet the demands imposed on it by the new environment. Making such modifications need not require engineering skills on a par with those of evolution: consider that it is much harder to design and build a car from scratch than it is to fit an existing car with a new set of
Ironically, given the Western diet, even if that is 'all' CR is, it may still be a good idea and life-extending.
From casual observation, paleo and intermittent fasting are the only diets that some people seem to like being on, as distinct from being burdens that some people think are worth the trouble.
I think part of the problem is that the question being asked varies. It matters what your aims are, (weight loss, general health, etc.) and what you're comparing it to. People tend to conflate:
For aim X, is Paleo better than the generic unstructured diet I've had up to this point? Probably yes.
For aim X, Is paleo better than a calorie and nutrient controlled diet based on all the available evidence? Probably not.
And what you mean by supporting it.
Is the paleo 'philosophy' that you should eat like in the ancestral environment always going to be best? No.
Is "eat more meat and vegetables and less refinied carbohydrates" a useful guideline for most people? Yes.
It looks as though some people are healthier if they eat some grains. One of my friends has even found that his digestion doesn't work well unless he eats a good bit of wheat. He hasn't experimented with other grains that include gluten. He's got a couple of relatives who show the same pattern.
I believe it's important to do your own experiments.
When I ask this question I am usually referred to Gary Taubes. Also see Wikipedia. I don't have time to evaluate the evidence, but I'm pretty skeptical of nutrition science in general.
Edit: Eliezer has spent a few years doing the only thing you can do: try a bunch of diets on yourself and measure the results.
Obviously, the reason I tried and am trying multiple diets is that the experimental result is always that nothing actually works. Except that the Shangri-La diet worked for twenty pounds and then mysteriously stopped doing anything (i.e., abrupt cessation of the diet did not result in any significant change in weight trends) and Seth Roberts couldn't get it working again. Paleo was among the diets tried, and it didn't result in any weight loss or other detectable differences. Non-US-approved, powerful, dangerous drugs like clenbuterol, which are supposed to cause weight loss on the order of a pound a day, produced standard side effects but no weight loss in me.
I figure that metabolisms vary at least 10% as much as minds, which is a HUGE amount of variance. It actually points up something I may post about at some point, which is that statistical science itself is often a dead end - you can publish paper after paper after paper about effects that show up in 60% of the population - but you don't know what separates the 60% from the 40% - and still have no real grasp on the phenomenon and no real ability to manipulate it.
It actually points up something I may post about at some point, which is that statistical science itself is often a dead end - you can publish paper after paper after paper about effects that show up in 60% of the population - but you don't know what separates the 60% from the 40% - and still have no real grasp on the phenomenon and no real ability to manipulate it.
I'd be very interested in such a post.
Have any of the diets you've tried produced changes (energy level, for example) for the better or the worse even if they haven't affected your weight?
A search through the NIH site does not seem to show a single reliable study on the subject...
The most obvious, and significant, argument in favor of paleo is that it tends to make it more difficult to overeat or maintain a lot of weight (i.e., it's acts as a fail-safe against akrasia). Imagine if you only had nuts, fruits, and vegetables to snack on and for anything else you had to cook a meal.
A better diet would be to push your eating window to 2-3pm to 10pm (intermittent fasting), and only eat low calorie things which you've cooked (and make sure you don't buy anything that can be eaten without being cooked).
Basically, from the research I've re...
I have a related diet question on portion size; I guess I'll ask here rather than the open thread or "stupid questions" thread. Is spreading out your carb intake over the course of the day as good as eating fewer carbs?
If the problem comes from glycemic load (spikes in blood sugar & insulin levels), then it seems like it should be. Instead of eating a big slice of pie in the afternoon, I could have half of the slice then and half at night. Or, even better, a bite of pie every 20 minutes. Then my body wouldn't be overwhelmed by a huge burst of pie all at once; the constant snacking would mimic the slow-release pattern of low glycemic index foods.
Hunter-gatherers eating traditional diets had very low rates of the modern "diseases of civilization" including cancer, heart disease and diabetes. When, however, hunter-gatherers switch to eating modern diets they start getting these diseases at high rates. (Of course this correlation doesn't prove causation, but still...) Also, anthropological evidence from bones show that populations usually became less healthy after adopting agriculture.
Although hunter-gatherers had lower life expediencies than we do, this was mostly due to them dying of s...
I switched from vegetarian to paleo based on Food and Western Disease, which had the best recommendations I could find at the time. I will take Dr. Linderberg's recommendations as what "paleo" means. Oversimplifying:
Yay: Lean meat, fish, veggies, root vegetables, fruit, some nuts. Drink water.
Boo: Grains, dairy, refined fats, sugar, beans.
The primary argument in favor of the 'yay' foods is nutrient density: you get a lot of micronutrients (and protein) per calorie. For instance, you want to consume about 100mg of calcium per MJ of energy you cons...
If paleo/primal advocates were strong rationalists, they would state the basic premise of the diet as follows:
"In the absence of evidence, the safest bet is to go with an ancestral diet."
And I think it is difficult to argue with that. When the evidence is mixed on a topic, it seems natural to default to tradition. In general I think paleo/primal dieters consider non-ancestral foods guilty until proven innocent...as in, you would have to present them evidence that a non-ancestral food was harmless and healthy before they started eating it. Most pe...
Here are some reasons why people might be better off eating less carbohydrates & more fat or protein:
*http://www.ncbi.nlm.nih.gov/pubmed/15148063
Compared with a low-fat diet, a low-carbohydrate diet program had better participant retention and greater weight loss. During active weight loss, serum triglyceride levels decreased more and high-density lipoprotein cholesterol level increased more with the low-carbohydrate diet than with the low-fat diet.
In addition, the low-carbohydrate group lost less lean body mass:
...Patients in both groups lost subst
We may soon be getting some real data. From Gary Taubes' blog: http://garytaubes.com/2012/01/updates-for-2012/
"Among the projects we have in the works is a non-profit, the Nutrition Science Initiative (NuSI), to raise money for the kind of research we think is necessary to clarify the relationship between dietary nutrients, obesity. diabetes and their related chronic diseases. We have a specific plan of research to pursue (or rather to fund so that established, unbiased researchers can then do the studies) and have already recruited a world class sci...
Many of the diets that appear to "work" (meaning reducing fat and supporting lean muscle mass) restrict carbohydrates, especially forms of carbohydrates that are rapidly metabolized. In my view, this commonality is much more interesting than the theoretical arguments for one diet versus another.
Anecdata: I have lost over 30 pounds since switching to a vaguely paleo (but really more carb avoiding) styles of eating last december. I track my weight daily, and cheat on saturdays, except a couple weeks ago when I cheated for the whole of Gencon. Very reliably, I gain weight after Saturdays, and gained 9 pounds over the course of Gencon. I tend to lose weight after days that I do not eat carbs on, and my lowest weight for a given week is almost always on Saturday morning. I do not track calories at all.
Anecdotal: the weight lifters / body builders I know say less carbs and more protein is helpful to their goals, and they say that paleo and/or Atkins is something to cycle through and not adopt as a lifetime diet. Three months of less carbs and more protein, three months of something else, three months of etc.,then if needed or desired three months back to less carbs and more protein. That time limit is something I see lacking in most discussions on the topic, and if I hadn't been told directly I wouldn't have known either.
Anecdotal: met a guy once who s...
Modern highly processed food is optimized to our sense of taste, to the extent that they can be called superstimuli. They are also correspondingly unhealthier, on many metrics. (I suppose this is the part in contention... I don't have any sources for this claim, sorry.)
The paleo diet, as well as the Atkins diet and other diets, inadvertently 'works' because highly processed foods tend to be carb-based (crackers, cookies, chips, sugary cereals, sugary yogurts, sugary soft drinks, sugary baked goods), and are thus excluded.
Right of the top of my head. Not all of them are scientific rigorous, just evidence that points against carbs.
A high carb diet was only introduced around 10k years ago with the invention of agriculture. As hunter/gatherers the diet was mostly hunted animals(protein/fat) and some occasional carbs from gathered fruits. So the human body is mostly adapted to protein/fat.
Methabolic pathways. Carbs once inside the body are broken down into sugar, which hasn't much nutritional value other than providing energy and the excess is converted into fat. Proteins c
I recently came out against paleo in the open thread, and realized that I probably haven't yet heard the strongest arguments in favor of a paleo diet. So, what are said arguments?
EDIT: Or more generally, why should I eat less carbohydrates and more protein / fat?