The Longevity Experiment
adventure.nationalgeographic.com
From National Geographic, Dan Buettner's search for the fountain of youth among the longest-lifespan cultures of the world.
adventure.nationalgeographic.com
Absolute nonsense. The only thing that has a clear relationship with extending lifespan is calorie restriction. The rest is very very unclear.
This guy finds a population, finds one thing they do that supports his preconceived notions of what makes you live longer, and then says that this population's behavior in this respect proves that this action makes you live longer.
So he finds a vegetarian culture that lives long and says OK vegetarianism makes you live longer. He finds a culture that drinks a lot of alcohol and says OK, alcohol doesn't limit longevity.
He finds a culture that eats a balanced diet, a culture that exercises a lot, etc. etc.
None if this is really any type of proof, and if you examine many different cultures, you will find his evidence is contradicted by other cultures (meat eating cultures that live longer and have fewer health problems than nearby vegetarian cultures, for instance).
Our knowledge of what helps humans to live the longest possible life is, sadly, very limited still.
And a bit of speculation: lots of heavy metals accumulate up the food chain. If you eat an onion, that's one onion's worth of heavy metals extracted from the ground. But if you eat a chicken leg, it's a few kilograms worth of plant that accumulated in it. And when you feed them animal protein it concentrates even further. Over a lifetime it's probably a difference of an order of magnitude between a meat-eater and a vegetarian.
zngtk4 is basically saying that nutrition science is sampling at too low at resolution to make definitive claims, I buy that.
How many times can you flip-flop on eggs until we stop listening? Obviously they're something else going on. The argument that they're generally "bad" is too low rez. Not to mention how we were told to eat margarine over butter for 50+ years, and it turned out to be one of the worse things to consume.
Raw foodists claim there's a lot of denaturing and damage done to proteins, enzymes and more when food is cooked. There are differences in composition between food that is cooked until done and food that is cooked until blackened (e.g. on a barbecue). Some claim there is measurable damage done when food is blended compared to chopped or juiced 'gently'. There is lots of skepticism about microwave cooking versus traditional ovens. As well as eggs, popular advice zig-zags on soy and types of fats. So...
>> zngtk4 is basically saying that nutrition science is sampling at too low at resolution to make definitive claims, I buy that.
I buy it too.
Observational studies that are peer reviewed and exhaustive can yield results that are entirely opposite reality. Dozens of peer reviewed, exhaustive observational studies told doctors that hormone replacement therapy reduced the incidence of heart attacks. Only after 16,000 women were enrolled in a double-blind controlled trial of hormone-replacement therapy in the 90s (after 6 million women had received the therapy) did we learn that heart disease, breast cancer, stroke, and dementia actually were more common in people receiving hormone replacement therapy vs placebo. In other words, the exact opposite.
Epidemiology is only of value in formulating hypotheses, not in proving anything.
Then they weren't exhaustive were they? Virtually nothing is proven ever. In fact, nothing is absolute except abstract mathematics. When there are numerous studies showing a correlation then we can feel somewhat confident in it. When we then look at disease rates in societies that do not eat me and see a clear correlation between meat eating and heart disease then we can feel even more confident.
Also remember that in the china study the group that got more disease (and ate more meat) got roughly the same amount of exercise and had roughly the same lifestyle. This isn't absolute proof, but nothing is every absolutely proven. I always find it fascinating that there is such a knee jerk reaction to this issue.
And the fact is, there are not numerous studies consistently showing a correlation, there are many studies that do not show that those who eat more meat get more disease. For example, Cretan villagers have lower heart-disease rates than even the Japanese and eat diets consisting of 40% fat. The "French Paradox" is so termed because the French eat high quantities of animal fat but have low heart disease. Tokelauan's, who had a diet high in fat (50% fat) and saturated fat (90% of the fat they ate was saturated), were relatively healthy. After migrating they consumed much less fat and had higher heart disease.
In other words, there's a lot about diet we don't understand yet and you can't boost the relevance of epidemiological studies by saying that "virtually nothing is proven ever" and therefore we should just accept observational science, when it's known that epidemiology has significant flaws as anything other than a hypothesis generator.
Now onto the french paradox. First, you again are conflating fat with meat. They aren't the same so at this point you seem to be pushing an agenda through bait and switch.
"French people get up to 80% of their fat intake from dairy and vegetable sources ... The principal aspects of this diet include high olive oil consumption".
There is plenty of evidence and there are some outliers. Using outliers to claim that the abundance of evidence doesn't exist is disingenuous. Also, the american diet is terrible for other reasons such as the high consumption of highly processed foods. One can certainly find people that eat a lot of meat, but little processed food, and show that it's a healthier diet compared to one of highly processed foods. This doesn't mean that a diet low in meat and processed food isn't healthier, and in fact we there is a good deal of evidence showing that it is.
There are animal studies that looks pretty compelling to me. The China Study refers to some of these.
Saturated fat has little effect on rats, but polyunsaturated fat induces tumors in rats according to to many studies. Low-fat, high calorie diets lead to more tumors than high-fat, low calorie diets in rats (in fact the high-fat, low calorie diets essentially stopped tumor production entirely). This latter was a major study in the journal Cancer Research. Only in high calorie diets was high-fat worse than low-fat, and in low calorie diets, high-fat was better than low-fat.
Atherosclerosis is often observed in pigs, cats, dogs, sheep, cows, horses, reptiles, rats, and baboons when fed exclusively vegetarian diets.
Monkeys in captivity often become fat and diabetic on high-fiber, low-fat, no-cholesterol diets.
It's entirely possible that a no-meat diet is best for humans, but I don't think we're anywhere near the understanding needed to say this -- and his recommendation to avoid fish as well would be viewed as dangerous by much of the medical and scientific community. What we really need are controlled studies, which are entirely possible to do.
I don't see how controlled studies are possible for various reasons. For starters there are far to many variables and we have no idea how they interrelate. Second, we can't control humans to the degree that would be needed to truly isolate a single variable (which I don't think would be too useful anyway) and animal studies are always imperfect. I'm convinced that diet studies are most effective when performed at a higher level of abstraction.
Er... Maybe you should read the book first before you go on a tirade against it.
Huh?
The first step is to think about who you hang out with. There’s no silver bullet for longevity. I’m not gonna tell you to take a pill. If your three best friends are obese, there’s a good chance you will be. Surrounding yourself with people who don’t smoke or drink too much and who have a spiritual component in their lives has a profound impact over time. Cut out the toxic people in your life and spend time and effort augmenting your social circle with people who have the right values and a healthy lifestyle.
I don't know why, but this snippet brought Robert Greene's The 48 Rules of Power to mind: "Infection: Avoid the Unhappy and Unlucky" (Rule 10). Of course, Greene's approach can be interpreted as a tad Machiavellian. But the message is still the same: watch who you're hanging out with. I've noticed that many of one's peculiar behavioral habits can be directly attributed to friends and acquaintances. It's interesting to see longevity talked about in the context of the people you spend time with.
"You are who you hang with."
I know sometimes when I'm feeling crap I look at which groups of friends I've been spending time with lately. Always scary stuff.
I appreciate not having to click through pages, etc. a little warning would just be nice.
What's really needed is an autopager/readability mashup.
I'm also not sure what you mean by "controlled". For example, in the china study the group that ate more meat was compared to a similar group in the same country with the same lifestyle. Isn't this the definition of a control group?
Obviously not. You just offered the definition of uncontrolled.
> climate change is just blah
Well he makes a pretty good point that data dredging for correlations is bad science. But the real reason climate change is "blah" is that the world isn't actually warming. Clearly shown for over ten years now by satellite and ground station data. There was only warming after a long cooling trend that lasted into the 70s.
http://jennifermarohasy.com/blog/2009/06/how-the-us-temperat...
More suitable for pondering than analyzing, IMHO.
It baffles me that anyone would entirely change their diet and lifestyle based on an epidemiological study.
I would argue that a broad, epidemiological study is the most persuasive sort of evidence to use when considering whether to make drastic changes. Otherwise you're dealing with information like "omega 3s prevent x, y, and z" so you end up taking an Omega 3 supplement along with the dozen other supplements while eating Wendy's for lunch every day.
Thinking that health can be understood on the basis of "taking supplement x is good" is the root of the current supplement gold rush (people sell tons of snake oil substances that contain "omega 3's" etc.) and a highly irrational way to behave.
Examining the processes isn't sufficient to provide proof unless it's a completely thorough examination. Biological science isn't at that point yet, and so what this usually means is that group A performs an observational study, group B finds a process that would explain group A's results, assuming group A's results are true. That's different from showing that group A's results were true.
Human, and animal, physiology is very complicated, and it's just plain wrong to assert that we know that eating meat decreases longevity. We don't. There is some evidence to believe it, and some evidence to not believe it at this point (both epidemiological studies and at the molecular understanding of the processes involved).
Epidemiological may be persuasive, but it's misleading because you take a single variable out of hundreds that may not even be known. So you may get Texans who become vegetarians based on longevity studies in some region of China, but then live an even shorter life because their lifestyles and the particular vegetarian foods that they eat aren't as conducive to longevity. This history of epidemiological studies are full of cases like this.
Clearly, humans can eat meat (during most of human evolution calories were scarce and eating meat conferred a selection advantage)...
But why would you reason that all foods are equally beneficial and harmful? To me, broad epidemiological studies can offer clues on classes of foods and some of the costs/benefits that they confer.
However the study that you call for has been done in laboratory animals -- TCC found that (controlling for calories, etc.) the animal proteins he studied led to the growth of cancer cells, while plant based foods did not cause cancer to develop, even in an environment of radiation, etc., that would typically be thought to be the cause of the cancer.
I fully agree that the study you mention would be hugely beneficial, but by your logic one ought to smoke cigarettes if one chooses, or at least ought to have done so in the 1980s before more conclusive evidence began to emerge... even though most doctors/scientists had held a strong belief that smoking was a bad idea for decades.
If one were to base all of his health decisions on studies that were conclusively done in humans (without regard for any animal studies, etc.) one would be limited to a 1950s understanding. Humans are not mice, and the studies don't all correlate perfectly, but many do. And they contain valuable (though not necessarily conclusive) information.
This is the main reason we are always hearing in the press about how a "study shows that X is bad for us" then a "study shows that X is good for us". The majority of the time when there are such conflicting studies, it is the result of epidemiology or poorly controlled studies.
These are blogs written by people who are promoting a high cholesterol diet -- hmm, ever notice that there is lots of money in promoting nutrition advice that confirms to what people are currently already doing?
T. Colin Campbell, Ph.D. has been at the forefront of nutrition research. His legacy, the China Study, is the most comprehensive study of health and nutrition ever conducted. Dr. Campbell is the Jacob Gould Schurman Professor Emeritus of Nutritional Biochemistry at Cornell University and Project Director of the China-Oxford-Cornell Diet and Health Project.
Dr. Campbell received his master’s degree and Ph.D. from Cornell, and served as a Research Associate at MIT. He spent 10 years on the faculty of Virginia Tech’s Department of Biochemistry and Nutrition before returning to the Division of Nutritional Sciences at Cornell in 1975 where he presently holds his Endowed Chair (now Emeritus).
Poorly written abstracts are the leading cause of sensationalist headlines.
X is observed in people doing Y is not a scientific breakthrough, it is an observation. If not all people that do Y have X there is no story, just more work to get to the bottom of what is going on.
Then why have lifespans gone up and heart disease declined all around the world in lockstep with animal protein consumption? Why do the two longest lived groups in the US (Mormons and upper upper Midwest whites) have high meat consumption?
from the source:
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The people inhabiting Blue Zones share common lifestyle characteristics that contribute to their longevity. Among the lifestyle characteristics shared among the Okinawa, Sardinia, and Loma Linda Blue Zones are the following:[4]
Family - Family is put ahead of other concerns.
No Smoking - Centenarians do not typically smoke.
Plant-Based Diet - The majority of food consumed is derived from plants.
Constant Moderate Physical Activity - Moderate physical activity is an inseparable part of life.
Social Engagement - People of all ages are socially active and integrated into their communities.
Legumes - Legumes are commonly consumed. ------
This isn't exactly true. There has never been much of a shortage of 75 year olds, excepting certain grindingly poor societies.
However, the problem isn't meat eating; it's the quantity and fat content of meat that is eaten. Eating moderate amounts of beef, chicken, etc, is associated with longer life and healthier hearts, but eating too much is associated with heart disease.
He also doesn't mention that another thing the groups all have in common is being alive at the same time - if treatment for symptoms improved, all ages would benefit, e.g. with the creation of the National Health Service (NHS) in Britain, starting with legislation in 1948 and presumably taking a few years to ramp up to nationwide usefulness.
I also read some more of the "articles" on that site you linked to and they were absurd on their face. Here is one example. They are attempting to refute the claim that animal farming is an efficient use of land.
"Much of the land used for animal farming, cannot be used for arable farming. With a rapidly expanding world population, a large proportion of whom are already starving, how can taking this land out of production help?"
This completely ignores the fact that large percentages of our corn and soy farming is used to feed animals. Ignoring this single data point either makes them ignorant or dishonest.
I'd go google up the data about heart disease declining in Japan and continental Europe in the post-war era, but I get the impression you're blind to facts.
Regarding land, if we used the land used to grow animal feed to grow plants for human consumption we'd get a lot more food. This is clearly more efficient, yet the page you linked to tries to claim the opposite by ignoring facts and building logic on that false basis.
Animal feed is only grown on this land because it is subsidized. Growing plants on it is economically inefficient. If agriculture in the US were unsubsidized, nobody would try to grow plants on this land. It would be grasslands. And the only human use for the land would be to graze animals on it.
I agree with you about the current absurdity of our system.
Dairy cows and egg laying chickens and farmed catfish are much more efficient at turning vegetable matter into complete proteins than humans. If you accept the premise that humans need almost a gram of complete protein per kg of body mass per day, animal production is more efficient and quite necessary.