Meat and cheese may be as bad for you as smoking

meat

That chicken wing you're eating could be as deadly as a cigarette. In a new study that tracked a large sample of adults for nearly two decades, researchers have found that eating a diet rich in animal proteins during middle age makes you four times more likely to die of cancer than someone with a low-protein diet—a mortality risk factor comparable to smoking.

"There's a misconception that because we all eat, understanding nutrition is simple. But the question is not whether a certain diet allows you to do well for three days, but can it help you survive to be 100?" said corresponding author Valter Longo, the Edna M. Jones Professor of Biogerontology at the USC Davis School of Gerontology and director of the USC Longevity Institute.

Not only is excessive consumption linked to a dramatic rise in cancer mortality, but middle-aged people who eat lots of proteins from animal sources—including meat, milk and cheese—are also more susceptible to early death in general, reveals the study to be published March 4 in Cell Metabolism. Protein-lovers were 74 percent more likely to die of any cause within the study period than their more low-protein counterparts. They were also several times more likely to die of diabetes.

But how much protein we should eat has long been a controversial topic – muddled by the popularity of protein-heavy diets such as Paleo and Atkins. Before this study, researchers had never shown a definitive correlation between high and .

Rather than look at adulthood as one monolithic phase of life, as other researchers have done, the latest study considers how biology changes as we age, and how decisions in middle life may play out across the human lifespan.

In other words, what's good for you at one age may be damaging at another. Protein controls the growth hormone IGF-I, which helps our bodies grow but has been linked to cancer susceptibility. Levels of IGF-I drop off dramatically after age 65, leading to potential frailty and muscle loss. The study shows that while high protein intake during middle age is very harmful, it is protective for older adults: those over 65 who ate a moderate- or high-protein diet were less susceptible to disease.

The latest paper draws from Longo's past research on IGF-I, including on an Ecuadorian cohort that seemed to have little cancer or diabetes susceptibility because of a genetic mutation that lowered levels of IGF-I; the members of the cohort were all less than five-feet tall.

"The research shows that a low-protein diet in middle age is useful for preventing cancer and overall mortality, through a process that involves regulating IGF-I and possibly insulin levels," said co-author Eileen Crimmins, the AARP Chair in Gerontology at USC. "However, we also propose that at older ages, it may be important to avoid a low-protein diet to allow the maintenance of healthy weight and protection from frailty."

Crucially, the researchers found that plant-based proteins, such as those from beans, did not seem to have the same mortality effects as animal proteins. Rates of cancer and death also did not seem to be affected by controlling for carbohydrate or fat consumption, suggesting that animal protein is the main culprit.

"The majority of Americans are eating about twice as much proteins as they should, and it seems that the best change would be to lower the daily intake of all proteins but especially animal-derived proteins," Longo said. "But don't get extreme in cutting out protein; you can go from protected to malnourished very quickly."

Longo's findings support recommendations from several leading health agencies to consume about 0.8 grams of protein per kilogram of body weight every day in middle age. For example, a 130-pound person should eat about 45-50 grams of protein a day, with preference for those derived from plants such as legumes, Longo explains.

The researchers define a "high-protein" diet as deriving at least 20 percent of calories from protein, including both plant-based and animal-based protein. A "moderate" protein diet includes 10-19 percent of calories from protein, and a "low-protein" diet includes less than 10 percent protein.

Even moderate amounts of protein had detrimental effects during middle age, the researchers found. Across all 6,318 adults over the age of 50 in the study, average protein intake was about 16 percent of total daily calories with about two-thirds from —corresponding to data about national protein consumption. The study sample was representative across ethnicity, education and health background.

People who ate a moderate amount of protein were still three times more likely to die of cancer than those who ate a low-protein diet in , the study shows. Overall, even the small change of decreasing protein intake from moderate levels to low levels reduced likelihood of early death by 21 percent.

For a randomly selected smaller portion of the sample – 2,253 people – levels of the growth hormone IGF-I were recorded directly. The results show that for every 10 ng/ml increase in IGF-I, those on a high-protein diet were 9 percent more likely to die from cancer than those on a low-protein diet, in line with past research associating IGF-I levels to cancer risk.

The researchers also extended their findings about high-protein diets and mortality risk, looking at causality in mice and cellular models. In a study of tumor rates and progression among mice, the researchers show lower cancer incidence and 45 percent smaller average tumor size among mice on a low-protein diet than those on a high-protein by the end of the two-month experiment.

"Almost everyone is going to have a cancer cell or pre- cell in them at some point. The question is: Does it progress?" Longo said. "Turns out one of the major factors in determining if it does is is ."

More information: Cell Metabolism, Levine et al.: "Low Protein Intake is Associated with a Major Reduction in IGF-1, Cancer, and Overall Mortality in the 65 and Younger but Not Older Population." dx.doi.org/10.1016/j.cmet.2014.02.006

Cell Metabolism, Solon-Biet et al.: "The ratio of macronutrients, not caloric intake, dictates cardiometabolic health, aging and longevity in ad libitum-fed mice." dx.doi.org/10.1016/j.cmet.2014.02.009

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Rimino
Mar 04, 2014
This comment has been removed by a moderator.
scottfos
3.8 / 5 (10) Mar 04, 2014
OTOH, rimino, you skipped right past things like "IGF-I" and "For a randomly selected smaller portion of the sample – 2,253 people" and "what's good for you at one age may be damaging at another" and "Levels of IGF-I drop off dramatically after age 65, leading to potential frailty and muscle loss", and went straight to the mice comment (which seems to be one minor aspect of a larger collation of data). maybe commentators should read AND think more, and nitpick less....
Mike_Massen
1.7 / 5 (7) Mar 04, 2014
The combinatorial complexity of several metalloid enzymatic issues does not seem to be considered, eg:-

- High rate of copper binding to prions
- influence of metalloid enzymes re protein degradation re antioxidant properties of copper based proteins
- co-antagonism of copper/zinc mettaloid enzymes
- deficiency issues of copper/zinc/molybdenum from regular processed food diets
- Any mettaloid issues at all, there appears to be preoccupation with non-metalloid proteins/enzymes
or rather complete disregard of the role of metals in conjunction with ANY proteins in these types of studies...

Eg For humans the amazing roles and requirements we have for the two key copper based enzymes of:-

- Ferroxidase
- Cerruloplasmin

These two alone, when understood in context with our western diet being 200 x lower in copper for millenia Must have import re so many derivative functions, yet completely ignored on a grand scale, and Moi as an engineer see this - others don't wassup guys !

?
JVK
1 / 5 (8) Mar 04, 2014
http://linkinghub...12002367

Excerpt: "...system biology approaches will become increasingly important to fully grasp the complexity of the connections between metabolism and chromatin dynamics. A deeper understanding of these connections may help shed light on our understanding of the etiology of a variety of complex diseases...

Nutrient-dependent/pheromone-controlled adaptive evolution: a model
http://www.socioa...53/27989

'...the model represented here is consistent with what is known about the epigenetic effects of ecologically important nutrients and pheromones on the adaptively evolved behavior of species from microbes to man. Minimally, this model can be compared to any other factual representations of epigenesis and epistasis for determination of the best scientific 'fit'."
TopCat22
4.8 / 5 (6) Mar 04, 2014
does this mean I should be eating more pasta?

Its very hard to know what to eat anymore... what about fish? is that good or bad? If fish is animal protein how come the Japanese live longest?
Jim4321
4.8 / 5 (4) Mar 04, 2014
They controlled for waist circumference. However, more carbohydrates increase appetite and obesity and presuably mortality. Wouldn't this attenuate their findings and lean towards the higher protein diet. Does anyone understand why they controlled for waist circumference?
Porgie
2.1 / 5 (15) Mar 04, 2014
This is so much left wing drivel. I find it hard to believe that the left is consistently trying to do away with eating meat protein for political reasons. I'm surprised that Physorg tolerates it. This happens all the time the left comes up with a study to end all studies then someone else straightens it out with the same statements, faulty logic, poor quality analysis, dubious data. Sounds like the global warming stuff doesn't it. The left has abandoned the scientific principal in lieu of the desperate political principal.
The Shootist
1.8 / 5 (15) Mar 04, 2014
This is so much left wing drivel. I find it hard to believe that the left is consistently trying to do away with eating meat protein for political reasons. I'm surprised that Physorg tolerates it. This happens all the time the left comes up with a study to end all studies then someone else straightens it out with the same statements, faulty logic, poor quality analysis, dubious data. Sounds like the global warming stuff doesn't it. The left has abandoned the scientific principal in lieu of the desperate political principal.


Nihilism. The left hates humanity, thus itself. So many of their grand ideas result in the deaths, or impoverishment, or starvation, of billions.
ziphead
4.8 / 5 (6) Mar 04, 2014
It has been known that low protein intake increases longevity somewhat (this goes hand in hand with calorie restriction). And of course, conversely, if you eat lots of charred meat every day, you should not expect to become a centenarian.

But I do have to question the alarmist nature of the find. "As bad as smoking?" If the impact of high animal protein diet is truly so great then:
Why was this not picked up by earlier studies? Surely this would have caused a blip in the epidemiological data all over the place?
Why is this not clearly reflected in the life expectancy of the high protein consuming countries?
Dug
5 / 5 (4) Mar 04, 2014
This is a low note in this discussion forum. "Protein" covers a lot of mixed variable ground - including fats, iron and hormone levels - all with their own separate disease risk issues. To base a study solely on animal protein, not even distinguishing the animal type or nutrition criteria levels is hopelessly gross - if not scientifically and intellectually naive - or worse - just plain incompetent. Or, perhaps they have a vegan or vegetarian agenda who believe animal protein sources are just plain evil all science aside. The fact that we are 3x5 times our species sustainability levels never seems to bother them.
dedereu
not rated yet Mar 04, 2014
Fundamental study confirming many others before, which must be followed if you want to live longer, and you must addd the necessity to make intense exercice every day, even being old retired, like me, running or cycling every day a steeply slope 200m difference in height.
As a real proof looks at the french 102 years old recordman cycling 27km in one hour .
TechnoCreed
1 / 5 (1) Mar 04, 2014
The title itself is bad journalism and an invitation not to take the article seriously. My appreciation; a strong 1, congratulation Miss Suzanne Wu your brilliance makes the University of Southern California shine.
http://news.usc.e...smoking/
dedereu
not rated yet Mar 04, 2014
As a proof, look at the french little 102 years old man recordman cycling 27km in one hour, faster than at 100 !!.
http://keepingsco...-record/

StillWind
2.2 / 5 (10) Mar 05, 2014
I can't imagine that anyone could take this seriously. What we have here is another waste of tax dollars to promote an agenda.
Sinister1812
2.5 / 5 (6) Mar 05, 2014
does this mean I should be eating more pasta?

Its very hard to know what to eat anymore... what about fish? is that good or bad? If fish is animal protein how come the Japanese live longest?


Who knows? Too many contradicting studies anymore... I don't pay attention to any of them. But some people jump right ahead and believe everything they hear or read.
Lordtimothy
3 / 5 (2) Mar 05, 2014
Everyone is different. I would say you should try several types of diets yourselves and see which one is best.......for you. Personally if I avoid meat for a period of time, the feeling of more energy and generally feeling better is there. However I love the taste of meat so I will always be eating meat.

vlaaing peerd
5 / 5 (5) Mar 05, 2014
does this mean I should be eating more pasta?

Its very hard to know what to eat anymore... what about fish? is that good or bad? If fish is animal protein how come the Japanese live longest?


Just a normal diet with fruits, grains, fish, meat, diary, veggies and fruits, vary as much as possible and don't be excessive. Wholeweat pasta's are generally more nutritious than the white ones, if prepared well a pasta can be very healthy. Also fish is in general good food and gets you a lot of vitamins and fat-acids (correct english?) you hardly find in other foods.

Such researches are good knowledge, but no need to panic and completely overthrow your complete diet. Process and junk foods are far more a problem than real, traditional foods. Just be sensible, moderate and enjoy.

The title "as bad as smoking" is also a little over-sensational.
kotyto
2 / 5 (4) Mar 05, 2014
Smacks of manipulation, first they messed with our earning power, exporting jobs out of sheer greed, now they hint at the "benefits" of a more modest diet.... I begun suspecting these "studies" being manipulative and made to order, either by pharmaceuticals note the various "trends", or by whoever pays the miscreants....
EnricM
1.3 / 5 (3) Mar 05, 2014
But for example the Innuits are adopted to their high protein diet quite well - they don't suffer with heart attacks more often than the rest of population. Sometimes the researchers should more think and less write about it.


I have read a study that contradicts that. I was searching but I haven't found it in Google Scholar yet (at work). In any case, de Inuit are not "adapted" to high protein, there genome is actually different (plus eventual epigenetic factors). This doesn't mean that the average guy from New Jersey should start chewing raw seal liver.

Mainstream modern humans happen to be genetically different from earlier hunter gatherer types and have been said to divert some 7000 years ago loosing.

And almost every study, including this one, fail to take the activity level / type of activity into consideration while this has an important effect on genetic expression related to levels of HGH, fat metabolism and other important physiological functions
Noumenon
3.5 / 5 (8) Mar 05, 2014
Being alive is the leading cause of death. Their is a strong correlation between having been alive and having not lived forever. In fact 100% of those who once lived, had eventually died. Since no one has ever lived forever, it appears that everything we do will eventually kill us. The goal should be moderation and exercise, to live well while we are living, and not be taken in by charlatans and blind correlation "studies".
vlaaing peerd
3.5 / 5 (4) Mar 05, 2014
I lived once, still do, didn't die (I'm hardboard). Your theory failed.

So, I'm not dead and I do drink vast amounts of beer,..(coincidence?) it's worth investigating.
dedereu
4 / 5 (1) Mar 05, 2014
Clearly, meat, milk cheese, beer, junk food, eaten or drunk, too much during too much years, with no sufficient exercice, is more bad than smoking, scientifically proven, when I see the number of deads and buried, quite younger than me, (retired since ten years), because of obesity, heart attack, cancers ....
Reading the comments, many, not convinced, prefer meat and cheese, to be alive older.

kochevnik
5 / 5 (1) Mar 08, 2014
The primary factor of these meats contributing to death is AGEs. Saturated fats were also though to be bad, but it was the AGEs made in preparation such as frying or grilling that made the oil deadly
Lex Talonis
3 / 5 (2) Mar 09, 2014
It's all bullshit - totally - unless you consider that it's ONLY Merikens eating Meriken toxic, hormone pumped, drug boosted, anti-biotic soaked chemical meats and cheeses.

LOL
Anonym
3 / 5 (2) Mar 09, 2014
@Lex: Exactly right. The study could be understood to show that middle-aged people who expose themselves to high levels of agricultural chemicals raise their mortality risk. The study does NOT show it's the beef itself, although of course the researchers posit a nice little biochemical model to support their belief it's the meat that's to blame. Possibly, the reason the elderly don't show the same risk is that they came up eating meat before it became a chemical matrix, and now they simply don't eat as much meat (or anything else) so their exposure is lower. At any rate, it's all bullshit --- totally.
Mike_Massen
2 / 5 (3) Mar 09, 2014
kochevnik makes arbitrary claims (again), is he to be trusted with
The primary factor of these meats contributing to death is AGEs.
Best top 5 references or indication of your qualification in dietetics or food science please?

Where is the tracking data, from volume consumed per demographic to death certificates including focused forensic autopsy data ?

kochevnik also claimed
Saturated fats were also though to be bad, but it was the AGEs made in preparation such as frying or grilling that made the oil deadly
Best top 5 references, which also cover acrylamides or indication of your qualification in dietetics or food science please?

Try to understand kochevnik, this is a SCIENCE site, arbitrary old man type random effluent complaints & barking to fill comment boxes does not make for considered opinions, peer reviewed references or representations from experience of data gathering in respect of your qualified path Please !

Mike Massen

Electronics Engineer & Food Scientist
jerryjbrown
4.5 / 5 (2) Mar 09, 2014
Maybe the solution is Bug Protein......hmmmmmmm. (I'm only being slightly sarcastic, cuz it may be true)
Returners
4 / 5 (4) Mar 09, 2014
Everyone is different. I would say you should try several types of diets yourselves and see which one is best.......for you. Personally if I avoid meat for a period of time, the feeling of more energy and generally feeling better is there. However I love the taste of meat so I will always be eating meat.


I'm the opposite. I feel empty and worn out if I don't eat meat.
DarkHorse66
5 / 5 (3) Mar 10, 2014
Everyone is different. I would say you should try several types of diets yourselves and see which one is best.......for you. Personally if I avoid meat for a period of time, the feeling of more energy and generally feeling better is there. However I love the taste of meat so I will always be eating meat.


I'm the opposite. I feel empty and worn out if I don't eat meat.

I'm the same. I find that I have less energy for the day. This is regardless of the fact that I do like my beans and other pulses (alot), which just happen to be a major source of protein (and hi-fibre too).
Cheers, DH66
Mike_Massen
3 / 5 (2) Mar 10, 2014
Returners admitted
I'm the opposite. I feel empty and worn out if I don't eat meat.
So often likely a combination of psychological & bio-chemical operant type conditioning, especially so as denser meats take more energy resources to digest for our useful digestive feedstock that simpler plant proteins.
ie You learn it by various psychological influences but don't know consciously how it occurs & thus represents itself to you as feeling not as a measure...

Eg. Have observed studies where people 'feel' lighter yet their weight increased & the converse, feel heavier yet weight reduced.

Food Science, which is one of my specialties covers aspects of foods which affect & influence mood, some can trigger addictive type responses. Its hugely complex overall but simple experiments have shown peer pressure, content & environment individually & collectively do influence food habits & can create the sense of tiredness/weariness which has also shown, in those circumstances, to be illusory.
DarkHorse66
5 / 5 (2) Mar 10, 2014
I do agree that meat should be eaten in moderation.No New York/Porterhouse steaks for me!(they are huge!..& expensive)
http://www.wisege...teak.htm
http://www.wisege...teak.htm
Here's some food for thought about eating too much meat, but also why eating at least some(but trim the fat)can be helpful.
http://www.rd.com...for-you/
I will pre-empt some of you by saying that,yes in a well-balanced vegetarian diet,one's vitamin&mineral needs are quite well covered.But a vegan diet is much more likely to cause deficiencies.Btw Mike, I have a question for you, you'v got me curious I know that mushrooms are the only non-meat source for B12, but do you know of any non-meat sources(esp in reasonable quantities of (acetyl-)L-carnitine orCarnosine? I need to take both for medical reasons&am curious about this, &yes they do deal with the issues that I take them for
http://en.wikiped...arnosine
DH66
Matto80
5 / 5 (2) Mar 10, 2014
@TopCat22

does this mean I should be eating more pasta?

Its very hard to know what to eat anymore... what about fish? is that good or bad? If fish is animal protein how come the Japanese live longest?


you can't single out one type of food for something like the fact that a group of Japanese people have the longest lifespans on average. Other things tied to that stat are: lots of soy products, fermented and non; active lifestyle in stress reducing ways like gardening. I'm interested in this story, but you've got to take it with a bit of critical distance. So maybe not so much pasta but more veggies an beans, exercise and fresh air... :)
gold2_718
not rated yet Mar 11, 2014
I think a lot of the issues are not in the study but in the press release and (lack of) editing by PhysOrg. The study itself does not distinguish between types of animal protein so the FUD at the top is made up, not reported from the article.

Also, the study did not make a comparison to death from smoking. More FUD from USC, not from the researchers.

http://news.usc.e...smoking/
Mike_Massen
3.7 / 5 (3) Mar 13, 2014
DarkHorse66 asked me personally
I know that mushrooms are the only non-meat source for B12, but do you know of any non-meat sources (esp in reasonable quantities of (acetyl-)L-carnitine or Carnosine?
Much exciting plant research ongoing, enthusiastic Food Scientists are generally dependent on contemporary research by plant biologists, that would be your best bet too.

Look at sea plants for greater variety, Eg. Kelp, sea grasses. Some land plants considered weeds in Australia eg. Purslane have unusual value re hormones but, some with caveats re high doses lead to kidney stones, suitable balance necessary, normal diet qtys handled well.

Easily get what you need from less onerous (easily digested) protein sources from seafoods.

The greater dietary problem is deficiency in metals (ie. Zn, Cu, Mo, Se) allied with bio-active compounds, eg anthocyanins.

Many Metalloid enzymes can moderate genetic issue re amino acids metabolisation in respect of signalling paths & companion enzymes.
kochevnik
5 / 5 (1) Mar 13, 2014
Glycation is even more dangerous to health than free radicals. Glycation interferes with cells' ability to get required amino acids from protein foods
Mike_Massen
1 / 5 (1) Mar 13, 2014
kochevnik's assertion could do with significant qualification
Glycation is even more dangerous to health than free radicals.
Really why ?
Who says ?
How precisely is it dangerous;
biochemical, bacteriological, structural, digestive, DNA, mRNA some actual references please kochevnik - this IS a science site. If you don't have handy references then the next best thing is to state your qualifications & career path in that particular area & point to Provenance, research etc ?

Awaiting a reply which is commensurate with knowledge not cheap & arbitrary opinion any plebe can spout off & totally without responsibility !

kochevnik again
Glycation interferes with cells' ability to get required amino acids from protein foods
What do you mean by 'to get' which biochemical pathways are affected, probabilistically ?
What are various byproducts ?
How is generation of ATP, ADP affected ?

Info man, this is a Science site, knowledge, details etc Or experiential career path Provenance ?
onlineteleshop2013
not rated yet May 01, 2014
Smoking and drinking is create the problem for the long life..

Full Stop Anti Addiction Powder for quit smoking
yourteleshopy.net

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