Please excuse the overly broad and lengthy question.
What if how we are eating is good for health and makes you a happy Crossfitter or Movnatter, but is not optimal for lifespan? Not that there is any one "paleo diet", but most of us eat lots of meat, some vegetables, limited fruits, and maybe tubers.
Many would rather have a limited number of happy years than be a calorie-restricted longetivity beanpole. On the other hand, many enjoy sandwiches and cupcakes, and are on paleo for overall health reasons despite it not being optimal for their tastebuds. What I'm getting at is that it is not a slam-dunk decision to go full-on paleo. I did it because of health issues, but for someone who loves food and eats fairly healthy, I'm not sure if "full-on" paleo is the best choice. Sure, restrict gluten, veggie oils, and fructose. But 80/20 or 70/30 gives you some delicious non-paleo meals if you "live to eat".
Here are some reasons why full on paleo might be not optimal for longetivity. This is presented as a devil's advocate argument, as there are many reasons that paleo is probably great for longetivity.
-Protein restriction for longetivity
-Neu5Gc- a molecule found in red meat that may or may not have something to do with cancer
-Dioxins- a toxin found only in animals products, even in organic pastured animals.
-Saturated fat- this is the weakest argument. Many of us probably eat more saturated fat than our ancestors did, when eating lots of coconut oil and the like. Those with familial hypercholesterolemia might take heed?
So here's the real question: I've seen more and more people being uber-strict paleo. I myself aim for uber-strict paleo. But in the halcyon days of youth, there were few things I liked better than a meal of a bacon-double cheeseburger on a kaiser bun with seasoned curly fries and a malted chocolate shake. We cannot know if being super strict outweighs the benefit of indulging sometimes (assuming you still enjoy wheat and sugar without guilting yourself to death). And people seem to follow what paleo experts say essentially right after they read it. Heck, when Kurt Harris hinted that he had upped his carb intake, some people wondered if they should add rice krispies to their diets too instead of analyzing his logic. Are we being too strict, following paleo leaders too blindly, discounting potential lifespan issues with paleo, or none of the above?
To whit, one of the most important predictors of lifespan has been how easy-going we are. Those who live past age 100 tend to have lower stress levels, regardless of diet. In fact, almost all ate some kind of junk food. (yes, selection bias here, but still...)
In answer to the question, "Is a Paleolithic diet the best diet for longevity?"..
As a doctor that has been promoting a high-fat, low carbohydrate, and restricted protein diet for almost 2 decades, I have long been saying that one cannot use paleolithic nutrition as a basis to determine optimal diet. Although a paleolithic diet may not be a bad diet and often is good(depending on which paleolithic diet one is talking about), the entire premise of using paleolithic nutrition as a basis to obtain an optimal diet is flawed.
Nature is concerned about reproductive success, not about significant post-reproductive health and lifespan. In other words, nature really doesn't give a whit about how long we live unless it pertains to reproductive success. Therefore, we cannot look to nature or count on nature or what's “natural” to tell us how to live a long healthy (post-reproductive) life. To obtain an optimal diet (as opposed to just a better diet that would be virtually any diet that deviates from the standard American diet) one must use modern science that one could even consider to be “unnatural”. (See short excerpt from my book below.)
The science of insulin and leptin clearly reveal that a diet high in non-fiber carbohydrates is extremely unhealthy and shortens lifespan. Furthermore, considerable and robust science tells us that excess protein (any protein beyond that necessary to build, repair, and maintain oneself) is equally detrimental (see links below to a couple of PowerPoints of talks I have given). Oil and fat is really the only relatively safe fuel to burn, and ones diet should consist mostly of this along with the necessary protein and minimal non-fiber carbohydrates, whether or not this sort of diet was paleolithic.
From p.46, "The Rosedale Diet" © HarperCollins ■ LONGEVITY ISN’T “NATURAL” "Within the billions of years that life has evolved on earth, we may have become smarter, more complicated creatures than our single-celled predecessors, but the fact is, we are here for pretty much the same reason. As Mother Nature sees it, whether you are a single-celled organism, a multicelled nematode, a bird, a dog, a cat, or a human, you are here for the primary purpose to reproduce and pass your precious genes (the library of life) on to the next generation. After that, you’re expendable. My patients are shocked when I tell them that there is nothing “natural” about trying to live as long a life as possible. You may want to hang around to be a healthy 120 and spend your last decades playing with your great-grandchildren, writing your novel, or traveling the world, but Mother Nature has other ideas. Mother Nature’s primary concern is to keep you alive long enough to reproduce, and maybe a bit longer after that to care for your young. That’s it. Some scientists believe that our cavemen ancestors followed an ideal diet for our health and longevity because they ate the “pure” and “natural” diet that we all evolved from. In reality, the so-called “paleolithic diet” followed by cavemen was not necessarily ideal for long-term health; in fact, it was sort of random. Cavemen ate whatever Mother Nature made available to them at the time. Keep in mind, Mother Nature didn’t give a whit about eating for a long healthy life; she just wanted cavemen to make more baby cavemen. You see why I say there’s nothing “natural” about the quest for longevity? If anything, in order to achieve longevity, you have to circumvent Mother Nature and consider some “unnatural” alternatives. By that I mean you have to “trick” Mother Nature at her own game.
Nature has very ingenious ways to help a species survive. When food is scarce, as it often was for our more primitive ancestors, in order to ensure the survival of a species, nature developed a method of keeping an organism alive through times of famine so that it could reproduce at a later, more opportune time. Reduced food intake turns on genes that protect the body against aging, allowing it to hopefully outlive the famine. Instead of spending lots of scarce energy to make babies that couldn’t survive, the body focuses its energy on maintaining and repairing itself. As soon as there is enough food available to support effective reproduction, the body switches gears and reduces its emphasis on maintenance and repair and directs its energy toward reproduction.
When you are in maintenance and repair mode, the body’s “body shop” is revved up and ready to go. Calorie-restricted animals have measurably higher levels of key chemicals that allow for extended life, protect cells from damage, and promote repair.
You don’t have to starve yourself to turn on the maintenance and repair switch. Following the Rosedale Diet will do the same good things for your body. How does it work? Leptin is a key player (perhaps in concert with insulin) in the evolutionary tug of war between whether the body should concentrate on reproduction or maintenance and repair."
...and to live a long, healthy, post-reproductive lifespan, we want our bodies to concentrate on maintenance and repair. To do that we must use modern science that tells us that we must regulate the hormonal nutrient sensors that, when kept low, turn up the genetic expression of maintenance and repair.
My comments to Stephan Guyenet responses to my answer on his site Dec. 4, 2009
Dr. Ron Rosedale said... Pertaining to insulin's primary purpose: Again, we must distinguish between controlling blood sugar and lowering blood sugar in a "normal" individual. Yes, I am well aware as are most people, that insulin can lower blood sugar. It does not mean, however, that insulin is controlling it. It is lowering the glucose levels as a side effect secondary to storing it as glycogen (little) and fat (lots), not to control the serum levels as we were typically taught in med school. The immediate regulation of blood glucose is left to epinephrine, norepinephrine, cortisone, glucagon, hGH, all of which control it in an upward direction primarily to make sure there is an anaerobic fuel available for emergencies. Just as we would not send a man to the moon with just one mechanism to deliver O2, we have many mechanisms to increase glucose, not lower it. This may be a very good clue of our evolutionary priorities. Furthermore, as far as glucose levels are concerned, a major role that insulin plays is to inhibit gluconeogenesis that would otherwise raise glucose by default, as seen in type 1 DM, as well as type 2, i.e. why they wake up with high BS even after fasting 10 hours. This may even be more to preserve lean mass than concern about high glucose levels in a normal, non type 1 DM individual. Also, I doubt there were enough type 1s in our evolutionary history for nature to give a whit about. Granted, however, that extremely high BS leading to spillover in the urine and dehydration as typically seen only in an uncontrolled type 1 diabetic along with severe acidosis would be selected against with relevance determined by the number of these individuals. Pertaining to all others with elevated glucose;: type 2 diabetics, impaired glucose tolerant individuals, anyone shortly after eating a typical breakfast of cereal and orange juice, etc.; the chronic diseases associated with this (i.e. all the chronic diseases of aging) including CAD and cancer afflict most people after having reached reproductive maturity. Even relevant parenting (especially in our ancestral history when reproduction was likely at an earlier age…) lies beyond evolutionary selective pressure. Thus elevated glucose would not have had great pressure to be selected against and may even have conferred advantages. Type II diabetes may therefore be an example of "antagonistic pleiotropy". Insulin's primary, evolutionary role was established billions of years ago—long before glucose was a significant part of our diet. Insulin in found in virtually all animal life, "down" to worms and yeast (where it also takes on IGF functions). It was certainly not used to lower blood glucose levels. January 7, 2010 11:56 PM
Dr. Ron Rosedale said... Thank you for your comment about leptin. I am also aware of leptin and its role in centrally regulating glucose, insulin, and most of the hypothalamic functions... I have written a book on this. Pertaining to maintenance and repair: The energy required for basal metabolic rate should almost entirely go to "maintenance and repair" such as the maintenance of body temperature, the maintenance of heart rate etc. Also, you mention moving muscles. Whenever that is accomplished, it damages the muscle and there must be repair of that muscle. I will quote from the recent article published in the journal Nature out of Linda Partridge's lab that you mentioned: "It [calorie restriction] is widely assumed to induce adaptive reallocation of nutrients from reproduction to somatic maintenance, aiding survival of food shortages.” -From: "Amino-acid imbalance explains extension of lifespan by dietary restriction in Drosophila", Nature, Dec 2, 2009. That was my assertion...that it is a popular and widely accepted (even "assumed") theory. Reproduction vs. maintenance and repair derives from Tom Kirkwood's very popular "disposable soma" theory... I think that the major point is being missed. I am talking about care and repair of the genome vs. its reproduction. The soma (body) is to take care of the genome until it can be reproduced and until it is environmentally/nutritionally advantageous to do so. Therefore all energy that goes into maintenance of the soma, whether that be for individual cells (outside of the nucleus) or the body of cells, until the genome can/should be reproduced, is energy for maintenance and repair. This allocation was apparently established during oceanic single celled life billions of years ago. Even so, the fact that M&R and reproduction are linked does not imply that it must be... the fact that it may be possible to unlink them does not mean that they were not linked or are not naturally linked… As far as Kitivans are concerned, one can debate all one wants about what ancient man ate or current societies eat... and it gets you no closer to determining the optimal diet (excepting that they may indicate what not to do). Diets evolved for reproductive success—not long, healthy, post repro life... for that we have no footsteps to follow. January 7, 2010 11:58 PM
I didn't start eating Paleo to increase my lifespan. I'm not even sure I want to get really old, even if I'm the cool grandma in jeans. It just doesn't appeal to me.
I started eating Paleo to get my trainer to stop talking about it. LOL. I never, ever thought I would do it for more than the 30 days. I was shocked at how much better I felt. Now, I eat this way because it has improved my health. I have "cured" a high blood pressure problem I had for 9 years. I wasn't expecting that.
I don't worry about the finer points at all. I enjoy reading and learning more about nutrition because I find it interesting, but I really just take the bits and pieces that work for me.
I don't strive for 100% uber strict Paleo. I don't want to be STRICT anything. I am really extremely happy exactly where I am at. It's weird to me because I have never been so totally happy with myself and my health and my body, but without plastic surgery, I'm just not going to fix anything to be better than it is right now. Accepting that took some time, but I really think I'm good.
I had pizza last week with my family out for a day at the movies. I squirt chocolate syrup in my mouth occasionally (ok, most nights) when I make my daughter's chocolate milk. I get a Jamba Juice when I get anywhere near one, which isn't often. Accepting that I'm not going to be perfect and learning to enjoy it instead of berating myself was HUGE, but I really think I'm there.
Let everyone ask a question to themselves: Why am I here, on this website, reading this question, reading the responses?
FWIW - I had been searching for a 'happier' life, because of a chronic low level fatigue, not looking good naked, unable to lose weight, stressed due to all above, recurrent minor infections and not getting satisfactory answers from the medical community.
Paleo/Primal, whether 90/10 or 80/20 or 70/30, whatever set-point I converged to, in my journey, has helped resolved all the above issues to a point of personal satisfaction wherein I am inclined to continue this way. Call it 'mind over matter' but I feel more in control this way, my stress levels about my own lifestyle are way way lower, in fact, I have almost stopped thinking how/when if I will die and whether this choice will become a cause for it. I am happy right now, I have been there done that (CW) and this is my currently chosen way to go.
Take heart kamal, we will all go one day. For now we have discovered a better path, we have discovered it because we are open to change, and in the future we will change again if necessary and convincing evidence is presented to us. There is no guarantee that any of us will take the next breath, Paleo or not. So lets rejoice life and enjoy the moment.
Here is another reason full-on Paleo may not be optimal. Despite our best efforts, we don't know EVERYTHING about what nutrients we need. It's very complex. We might think that Paleo is the "diet to end all diets" but that's just based upon what we presently know. For that reason, I think it's important to sometimes eat outside the box! In other words, eat more widely than we normally do in order to get some nutrients we might be missing. I am not saying that at such times we should eat complete garbage (like Twinkies), however, eat reasonably clean food that is not Paleo. Of course, eating an occasional nice piece of cake is a good thing, too. If nothing else, it will help you from becoming a food fascist.
None of the above.
Although I cant speak for all, I'd say most paleo-ers are pretty knowledgeable about diet, fitness, and general health issues. They (we) would rather die at a normal, age but physically fit and active, than live an extended life looking out the window in a nursing home.
I say have a little fun. A 95% near perfect diet with occasional cheats is longer to sustain, extreme diets are often abandoned.
I spend my days hanging out with a 95 year old Spanish woman who never cared about her health (she looks far better than a female version of Jack Lalanne at the same age regardless), dietary advice from her: everything in moderation; she does eat bread and legumes... no crossfit, no movnat, no pressups, pullups... just farm work... actually her pace of life is slow, but in short bursts intense, most of the time she spends just sitting talking, some gathering beans etc - if there is anything to be learnt from her?
I pretty much follow 80/20 (I should probably strict up for my current goals) but when I eat something non-paleo I follow one rule: I must LOVE it! I've never been a fan of chips, pastries, cakes etc so I just don't eat them even if it's there. I'd rather eat a really awesome sandwich or a delicious piece of bbq chicken or white pizza from the whole foods pizza bar. That's my advice- make sure everything you eat is DELICIOUS, especially your non-paleo indulgences!
Here's the way I think about it.
Set the same standard for two diets: full-on paleo eating on the one hand, and paleo with occasional neolithic indulgences on the other hand. So in one corner we have the diet that never includes the NAD; never includes an occasional meal with potatoes deep-fried in soybean oil, and never includes a white-flour sesame bun. In the other corner we have the diet that has a 20% share of such things, or let's say a 10% share of them. Now, sure, it might be the case that since evolution only cares about us until we reproduce (leaving kin selection to the side for the sake of argument), neither one of these diets will do anything for longevity. But ask yourself this: if you had to choose one -- and, well, I guess you do -- which one would you choose? How likely is it that we would have been rolling along with our natural selection-given bodies, dying early sad deaths, until we started screwing with the genes of wheat plants and pressing oil out of corn and making that 10% of our diet -- at which point, voilà, we started living much longer? It's possible, I suppose, but if I were a betting man -- and, well, I guess I have to be -- then I would put my money on the strict paleo.
But of course that's all other things being equal, including stress levels. If eating 100% instead of 90% causes you stress, then it may not be worth it. But I have a comeback for this one also. Since my entrance to the world of paleo was through Mark's Daily Apple, I've always considered stress-reduction to be part of the package; it's one of the 10 steps. So no matter how you cut it, paleo is the way to go. (I realize I'm being a little tricky here, but hey, it's fun.)
We have the one diet in the world, with Long Term evidence.
The only one based on Evolution...
I hate to bang our own drum, but in what dimension does processed food exceed what we evolved to eat?
Longevity is not solely about Food. On the food front I have no doubt that Whole Food and Toxin avoidance is optimal. But there are many more issues to be concerned with after food...