Paleo and "blood type" diets

[Martha]

My dearest friend has a science backround and is married to a person with a science backround. She was my roommate in my college years. We were vegetarians. She is thin and always has been thin. Her bad choresterol has always been low. She got breat cancer 5 years ago, but has been healthy since.

Now, years later, after her bout with cancer, she and her DH are pushing hard for the paleo diet and try to get Greg and I to convert. Basically, you eat what paleolithic man ate--meat, vegetables, fruit and nuts. This is the natural way to eat. No grains, potatoes, or beans. Never any milk, not even skim milk. It feels like the South Beach/Atkins type diet dressed up a little different. She is now starting to talk about a "blood type" diet. The basis is that because blood types evolved at different times through history, you should eat what was typically eaten when your blood type evolved.

Me, I could live on beans and lean closer to a vegetarian diet. I basically think that you should eat organic whole foods to the extent you can and practice moderation in amounts and types of food you eat.

I try to avoid discussing this much with her because she can be quit adamant in her beliefs. And so can I. I think this is bunk.

But she has given me several proported scientific articles in support of the paleo diet. I decided I want to be able to speak intelligently with my friend. Anyone have any ideas as to sources of good reliable information on these sorts of diets? A google search isn't giving me much more than those who are promoting those diets and those who poo poo them. No science.

 

[cute fuzzy bunny]

Didnt primitive man live about 19 years?

My uptake after seeing almost everything bunked and debunked, is that every diet, additive and special food is crap, everything causes cancer and everything is bad in excess.

I decided I should just eat a good balanced diet with a reasonable amount of lean meats, vegetables, grains and whatnot, limit obviously bad stuff like huge hunks of fat laden meat, lots of booze, white sugar, anything with corn syrup in it, and anything overprocessed.

I think the exercise piece trumps the diet piece most of the time.

I'm still certain i'm going to turn on the tv 10-15 years from now and see a story pop up "Broccolli...the silent killer..."

 

[cute fuzzy bunny]

http://en.wikipedia.org/wiki/Paleolithic_diet

 

[Martha]

I agree with you CFB on the balanced diet but I need SCIENCE.  I did read the Wikipedia discussion but there wasn't much there.  I would like to see something that shows that whole grains and beans are good for you. 

I have made the argument about how long primative man lived.  She says most of the dying early was due to injury and child birth.  If you managed to get through your younger years, you could have lived to be quite old.  But of course they did get lots of physical activity, odds are were not overweight, and  they didn't have a pile of chemicals in their their food and in their air.

 

[Texas Proud]

I am with CFB...

But, I have not meet anybody no matter what diet they have live much older than others... eveybody dies eventually... diet as a risk factor is still low

 

[laurence]

I think the exercise piece trumps the diet piece most of the time.

I'm gonna pull a CFB, "DING DING DING, We have a winner!"  

Seriously, I would love to see a study where they take a pool of people on one of these new age diets and compare them to people who don't smoke or drink  ten beers a day or mainline cheeseburgers and excercise three times a day and see which is better.  Sure, compared to the general population, these diets always look great, but that's because the average Joe is doing just about the worst things he can to his body!

 

[Martha]

My friend's diet isn't a bad diet. The meat protein she eats tends to be low fat, and she eats lots of fruit and vegetables. I just think that other diets can be good too. Including ones that include grains, beans, potatoes and milk.

Maybe it is her way of keeping the cancer monster at bay.

I want to be able to have a good scientific counter arguments to her attempts to convert me.

 

[Martha]

Personally, I think genes are the number one factor in how long you live. Oh, and not poisoning yourself, like through smoking. And you can do battle with a good diet and exercise.

 

[cute fuzzy bunny]

There can be no good science, unfortunately.

The problem with diet analysis is that its unsupervised and...well...people lie about what they eat, how much they exercise and whatnot. Heck, I know "non smokers" who smoke a half a pack of cigarettes a day and swear that such a small amount "doesnt matter". :

IIRC and perhaps Steely Dan can confirm as I think he has some knowledge in the matter, lots of primitive people ate meat as their primary food item, I believe milk has been in the diet for quite some time, since we all nurse on it and I'd imagine young paleolithic mothers, in the absence of lots of experts telling them to cut it out, nursed their kids well past six months or a year. And I think some north and central american "early dwellers" did have corn and beans as part of their diet.

The good news is that there doesnt appear to be any scientific support for the paleo diet either, except some anecdotal stuff about what we think early peoples ate and whether or not that was good for them...or us.

As far as development, a 375lb NFL lineman would have been a freak just 50-75 years ago. Now they're commonplace. Six foot tall men in the late 1800's were "big men".

Not to mention an adherence to a diet like the paleo one would mean that we'd have to let go of about 2/3 of the worlds population as grains, potatoes, rices and so forth are staples of most of the worlds diets.

 

[wabmester]

Martha, there is no science to support these diets.

First, cavemen didn't live very long.

Second, you need to understand cancer before you can understand dietary effects on cancer.

Third, there are basically two kinds of science when it comes to diet/health: large epidemiological studies and studies that try to look at mechanisms.

There have been no epidemiological studies looking at the fad diet du jour.    And the results of the epidemiological studies that have been performed are all over the map.

If you want some good science, look at the results from three perspectives:

1) Check out T. Colin Campbell's "The China Study" for a nice mix of epidemiology and mechanisms.   His broad epidemiological study suggests that diets low in animal fats and protein protect against a wide range of diseases.    One of his studies looked at a particular form of liver cancer for mechanisms, and he found that casein (milk protein) was a promoter of cancer that had been initiated by aflatoxin.    He'll tell you the mechanisms.

2) Check out various medical doctors (like Dean Ornish) who use diet in therapy for heart diseases and cancer.    They publish their results, and none of them are feeding their patients a bunch of raw meat.

3) Check out the subfield of gerontology that looks at the mechanisms of aging.    There are a bunch of mechanisms such as free radical damage, cross-glycosylation of proteins by carbs, etc.    The only thing that sort of works against these mechanisms is a low-calorie diet with sufficient nutrients.

 

[Martha]

CFB:  I read  that people used to be uniformly lactose intolerant and only recently have large numbers of people been able to digest milk after childhood.  Apparently many Asian people are still lactose intolerant.  But that in my mind is a "so what" fact.  If I am not lactose intolerant it doesn't matter and I can drink milk.

I'll wait and see if "Steely Dan" shows up with any thoughts on the primitive peoples.

Wab:  Thanks for the leads. 

 

[cute fuzzy bunny]

You mean there were primitive peoples outside of America?

GW's been lyin to me!



Completely true. I thought that goat and sheeps milk played a pretty big role in a lot of middle eastern and northern african diets early on, but i'm not really much of an expert in that area. Seems to me their diets are well laden with cheeses, yogurts and whatnot.

 

[Nords]

Maybe the paleo diet was originally marketed by saber-tooth tigers who found that it made their organic free-range caveman diet taste more yummy.

I try to avoid discussing this much with her because she can be quit adamant in her beliefs.  And so can I.  I think this is bunk.

The scientific documentation behind the paleo diet is in the National Archives, with Nicholas Cage's "National Treasure", Indiana Jones' Ark of the Covenant, and the 100-mpg carburetor.  The diet is being kept a secret until the shadow governmentt figures out a way to tax our new 150-year longevity and change the Social Security eligibility rules.  And the Plunge Protection Team is gonna have to come up with a new way to protect the stock market from all of us long long long term investors.

I think the fact that neither you nor your friend can find any reputable, reproducible studies in any major medical publication is all the evidence you need.  Heck, even the mainstream longitudinal studies are struggling to document the benefits of various diets, and some of them have been going on for decades.  Debating the paleo diet with your friend may be like debating SWR with *****.

However your friend's diet resembles the Wilcox's Okinawa diet, which is at least backed up by Japanese birth certificates and health records.  Maybe the two of you can find common ground there.

Frankly it resembles a local diet.  Not too much milk, no potatoes, hardly any rice, lotsa fruits & nuts & veggies with my tofu & yogurt.  Not sure how poi fits into her lifestyle, though, and I won't completely give up spaghetti or macaroni.

 

[cute fuzzy bunny]

interesting snippet on why the okinawa diet might work:

a low-fat diet, exercise, stress management, strong social and family ties, and spiritual connectedness

In other words, a lot more than diet alone. Also a lot of the folks are islanders that might have a differing and localized genetic makeup that might have something to do with their health and longevity...

 

[laurence]

African tribes have been drinking milk from hearded animals since the dawn of time, the Maasai are still doing it.  It's interesting to note how tall the Maasai are.

 

[sgeeeee]

Well . . . I've spent a lot of time studying archaeology over the past several decades.  We don't really know too much about the paleo diet.  We know that paleo man was a hunter gatherer who followed and killed large game animals.  He did not develop any substantial agriculture practices, he did not develop sedentary habits so he also did not develop substantial architecture or ceramics.  He may have gathered wild grains as well as fruits, nuts and herbs, but since the paleo-to-archaic transition occured about 7000 years ago, little evidence of this would be left in the archaeological record.  While people often tend to think of these people as dumb cavemen, the truth of the matter is that paleo man had the same brain we have.  He showed brilliant artistic talent and expert technical skills with stones, wood, bone and antler (the technical materials of the day).  Paleo man would have gotten a lot of exercise following the herds of large mamals and lived a hard life.  I'm not aware of any case of paleo skeletal remains that would support an idea of life lasting longer than about 30 years.  I just don't see much information in the archaeological record to base a modern diet on.

DW has a BS degree in Hospital Dietetics.  She practiced this science as a dietician in various high profile hospitals (including Stanford Medical Center and Mayo) for several years.  While she was practicing, we subscribed to several medical and dietetics journals.  We both read and studied these journals.  Reading this technical literature taught me:  1) that esentially everything lay people think they know about diet and absolutely everything printed about diet in popular sources is BS.  2) There is no use arguing with them.  Their knowledge is like religion.  

I remember, for example, one of the first articles I read in American Dietetics Review (I think) was a review of research on coffee.  The article claimed that caffiene was the most highly researched food in the world.  It cited and quoted hundreds of scientific studies.  Then pointed out that the conclusions were largely contradictory.  The reason was because food has such a second (or third) order impact on most people's health and longevity.  Genetics and lifestyle impacts on these issues completely swamp food most of the time.  Since we do not completely understand the impact of genetics and lifestyle, we cannot adequately remove these factors from investigations on food.

Good luck with your friend.  

 

[wabmester]

If you don't want to do a bunch of research, you can probably create your own pop-science argument.

The caveman diet is based on the premise that we did most of our evolving on some specific diet, right?

Evolution only works at the population level, and only on those members of the population who are still procreating like crazy.

Most of the diseases that kill us these days are the progressive diseases of old age.    Evolution has *nothing* to say about old age, because selection doesn't work on old people.

We evolved a bunch of different metabolic pathways.    We can eat carbs, fat, protein, and alcohol.

We evolved a bunch of repair and defense mechanisms.   We can repair some DNA damage, and we will attack foreign bodies in our bloodstream.    That tells us that our ancestors ate a bunch of crap and got lots of infections.

That's about as far as you can get based on cavemen: we're omnivores, we can take abuse, and we have few defences against long-term progressive diseases of old age (like cancer, heart diseases, etc). After that, we're on our own. The cavemen can't help us.

 

[HFWR]

But we've all passed a lot of gas water since then...

I'm no expert, but I'd bet paleo humans ate whatever they could find that wouldn't kill them. Heck, they probably ate everything in an animal, including fat, that was ingestible...

 

[brewer12345]

DW has a BS degree in Hospital Dietetics.  She practiced this science as a dietician in various high profile hospitals (including Stanford Medical Center and Mayo) for several years.  While she was practicing, we subscribed to several medical and dietetics journals.  We both read and studied these journals.  Reading this technical literature taught me:  1) that esentially everything lay people think they know about diet and absolutely everything printed about diet in popular sources is BS.  2) There is no use arguing with them.  Their knowledge is like religion.  

SG, given your past reading, it sounds like diet is a relatively minor effect of longevity and health, assuming one does not go to extremes.  What would you/your DW suggest as a general "good" diet?  Everything in moderation?  Something different?

 

[laurence]

I'm no expert, but I'd bet paleo humans ate whatever they could find that wouldn't kill them. Heck, they probably ate everything in an animal, including fat, that was ingestible...

Good point, hey Martha, how many insects has your friend added to his/her diet?  Grubs were probably a mainstay!  

 

[Outtahere]

And don't forget all the exercise they managed to get in their day by either running after their prey or being chased by it. Not to mention digging for roots, searching for water, climbing trees and bushes for nuts and berries.

 

[Martha]

 Genetics and lifestyle impacts on these issues completely swamp food most of the time.  Since we do not completely understand the impact of genetics and lifestyle, we cannot adequately remove these factors from investigations on food.

Good luck with your friend.  

Thanks SG, interesting stuff.  We aren't talking about eating too many processed foods and burgers.  We are talking about whole grains, beans and taters.  

If you don't want to do a bunch of research, you can probably create your own pop-science
Most of the diseases that kill us these days are the progressive diseases of old age.    Evolution has *nothing* to say about old age, because selection doesn't work on old people.

         *      *     *

That's about as far as you can get based on cavemen: we're omnivores, we can take abuse, and we have few defences against long-term progressive diseases of old age (like cancer, heart diseases, etc).    After that, we're on our own.   The cavemen can't help us.

Good, simple to use counterargument.  

 

[Texas Proud]

Just like most animals... they spent most of the day find food and eating... not much else to do..

And being no expert.. I do remember seeing a study on the risks of death.. and the only item that had a big impact was smoking... almost all other risks were almost non-existent (small)..

 

[samclem]

Martha,
Sorry, no science for you here, just an extension of wab's observations:
-- Longevity, beyond a certain point, is subject to adverse natural selection pressures. Once an individual is beyond child bearing/child rearing, there is very limited advantage to the overall population for them to hang around and consume resources. Humans already have an extraordinary lifespan beyond their normal childbearing years, but this is largely a modern occurence (brought largely by improved nutrition).

 

[Martha]

According to the Wikipedia discussion on life expectancy (FWIW), the biggest increases in life expectancy came from the reduction in infant mortality.  Though sewers didn't hurt.
http://en.wikipedia.org/wiki/Life_expectancy


My friend's argument against eating grains/legumes/potatoes has also to do with glycemic load and that these starches do a big sugar dump on you which is bad for you.