Seven million years of human evolution were dominated by two challenges: food scarcity and cold. “In the last 0.9 inches of our evolutionary mile,” they write, pointing to the fundamental lifestyle changes brought about by refrigeration and modern transportation, “we solved them both.” Other species don’t exhibit nearly as much obesity and chronic disease as we warm, overfed humans and our pets do. “Maybe our problem,” they continue, “is that winter never comes.”
৪ জানুয়ারী, ২০১৫
The "Metabolic Winter" hypothesis.
"[O]besity is only in small part due to lack of exercise, and mostly due to a combination of chronic overnutrition and chronic warmth."
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Good thing this problem hadn't been discovered yet back when LBJ was solving our unbridled-growth problem, or he'd have fixed it along with.
Chronic overnutrition. I guess that's one way to put it.
I Work outside doing construction work.And I have had many co-workers say that they tend to lose eight during the Winter. I myself know that I lose weight during the winter. And I attribute part of that to the fact that im not drinking 4 or 5 [ or more] Gatorades or juices during work, during the Winter.Like I do during the Summer
Which makes sense. Since your when your body is cold, it burns off a lot of energy to keep warm.And a person wants to work hard when its cold.Just inorder to keep warm[ The Summer is the opposite]
I think that those people that do gain weight during the Winter, are people who work in offices and aren't able to jog or walk when they get off of work [due to early darkness]
What we are missing are worms and other parasites. Used to be you needed to eat for at least a hundred. I'm waiting for a government regulation here...
Global Warming strikes again!
WTF? Most of humanity isn't too cold; it's too hot. Please, look at what fraction of the global population is between the tropic of Cancer and the tropic of Capricorn, and get back to me.
The author's thesis is fine so far as it goes, but that isn't far at all. A/C matters much more, to many more people, than does heating.
"Chronic overnutrition. I guess that's one way to put it."
I'm currently reading a cook book written in 1897, the Fannie Farmer Cook Book. The first chapter is nutrition information from that era. The recommended daily ration for an adult male was 3 1/2 Oz of protein and 10 Oz of carbs. I want to emphasize that is per day, not per meal.
The problem is not only overeating, but consuming the right combination and proportion of nutrients. The relevant issue is not necessarily temperature, but how it affects our activity. People enter a pseudo-hibernation period during winter. Also, reduced sunlight causes malnutrition. It may be necessary to consume a Vitamin D supplement.
And in 1897 you're going to be burning a lot of calories. Not a lot of labor saving devices. The second chapter addresses how to build a fire to cook with.
I don't understand if you have to FEEL very cold. For instance, I walk in tank top and shorts when it's in the 50's, but I don't feel cold. For the cold to speed up my metabolism over and above what walking does, do I need to walk in a tank top while it's in the 30's?
TV reporter Andrea Canning, when she was at ABC (she's now at NBC), once did a story on something called "thermal dieting":
https://www.youtube.com/watch?v=xvOBQOHZR2E
BRRRRRR. And while we're on the general subject, I saw the movie "Big Eyes" yesterday, and before the film, the theater showed a commercial for Weight Watchers which I found painfully funny as well as entertaining:
https://www.youtube.com/watch?v=GNPLuSx_06U
"Used to be you needed to eat for at least a hundred"
We are eating for billions !
The gut microbiome, while known to be enormous, has not in the past been considered as a metabolic role player in the body. This is now recognized to be the case. Recent studies have found the obesity is correlated with an alteration in the gut microbiome. In obese individual there is a change in the relative proportions of the two major classes of bacteria - bacteroides and firmacutes - with the latter dominant in obesity and resulting in the formation of increased amounts of metabolic endotoxins like deoxycholic acid and lipopolysaccharides (LPS)
You change your gut flora when you use sweetener instead of sugar in your coffee. This will be the biggest thing in medicine for the next 50 years.
I think the notion is an old one, related to the ideas of Julius von Mayer* who first noted a connection between body heat, metabolism and environmental temperature. What the new theory lacks is demonstrative link between global warming and obesity.
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*We owe von Mayer a great deal; it was he who first formulated the First Law of Thermodynamics: A Conservative Notion of Energy
Our bodies were never designed to consume large quantities cane sugar and high fructose corn syrup. That, and lack of regular aerobic exercise, are the two primary factors that are causing the record levels of metabolic syndrome (the precursor to Type II diabetes) in this country, particularly among the young.
I can see more of a downside to being cold and hungry than to being warm and well fed. It's also better to be young and rich as opposed to being old and poor, but perhaps further research needs to be done in this area.
Nothing wrong with getting overnutritious on cheeseburger and pepperoni pizza shooters.
In which theory lies the explanation for the hoardes of fatties in the frigid upper Midwest.
William - it's better to be young, rich, beautiful, smart and healthy! Better yet to have the ability to stay in that condition FOREVER!!!!
Michael said...
In which theory lies the explanation for the hoardes of fatties in the frigid upper Midwest.
It's all those fried cheese curdles.
chuck said...
"What we are missing are worms and other parasites. Used to be you needed to eat for at least a hundred. I'm waiting for a government regulation here..."
That is the problem. The parasites no longer live in our gastrointestinal tract. They moved to DC.
So, gradual warming of the planet would be good for humankind?
Which is why in the early times people from the tropics and their dogs were always obese.
Meade should have shoveled the walk wearing shorts.
So, gradual warming of the planet would be good for humankind?
Considering that we are in the middle of an ice age? yes.
Remember folks, in geological terms, there was a mile of ice on top of Detroit yesterday, and there could be again tomorrow.
"Herein, we discuss a novel way to view the major food macronutrients and human diet in this era of excessive caloric consumption, along with a novel relationship among calorie scarcity, mild cold stress, and sleep that may explain the increasing prevalence of nutritionally related diseases."
It's a "Just-So" story. I'm too lazy to look; do they have any actual data?
Do we really succumb at a younger age today than before the general introduction of central heating? I know, let's get the opinion of John Keats.
It is sort of an optimization problem. What is a gain in one area is a liability in another.
Interestingly enough evolution can contribute also to solving the problem. Those of English extraction can generally tolerate obesity without succumbing to diabetes better than others, say, for instance, the Japanese. The English 'lived' through a period some centuries earlier of significant food availability and so had those more susceptible die of diabetes thus favoring the persistence of genes favoring greater tolerance of obesity.
It's always interesting when what's interesting to people are theories that dovetail precisely into the tolerances and preferences of the people who put forth the theories.
Isn't it?
The most obese of the developed countries is the USA, but #2 is Mexico -- yes, really. They've always been warm but only recently have they become obese. Increased consumption of sugar and refined carbohydrates is IMO likely to be the main cause.
Pete From Baltimore -- I got serious about losing weight about 18 months ago and have since dropped about 25 pounds. One of the changes I made was to quit drinking fruit juice. I used to think it was the healthy alternative for coffee breaks. Now I think it's just sugar water colored with some cooked-out pulp, and suspect I dropped four or five pounds just from that change alone.
His observation that being in cool water burns calories is nothing new. I always lost weight when I went scuba diving. IIRC, it's about 3000 kcal per hour underwater, all due to the increased heat loss from the water.
The gut biome hypothesis has some experimental validation in rats, and observational evidence in humans. It's also hypothesized that it may be a real epidemic - the time history of obesity in the US shows a growth from a focal site in the US South, and a spread from there. (And it's not artificial sweeteners that is the culprit, they just mimic the effects of simple carbs.)
Don't forget the shift from saturated fats to carbohydrates.
Are there a lot of fat people on the equator?
The "ice vest" looks to me like just the latest crazy weight-loss fad. For a few years everyone will be wearing an ice vest. After that--no ice vests. Sort of like Crocs--remember those?
Charlotte Allen
"Meade should have shoveled the walk wearing shorts."
Meade walked all over the frozen Lake Wingra with the dog yesterday when the windchill was minus 10. My concern is that he'll get frostbite.
So now, cold and hungry is a good thing. The homeless have been leading the way.
I think exposure to cold makes you eat more as the body tries to protect itself with a layer of blubber. I'd read that swimming isn't good for weight loss for this reason. The example of Michael Phelps is absurd. You don't theorize from the outlier.
Meade walked all over the frozen Lake Wingra with the dog yesterday when the windchill was minus 10. My concern is that he'll get frostbite.
Then maybe you shoud knit something for the dog. And get him some booties too.
"Then maybe you shoud knit something for the dog. And get him some booties too."
He's a Lab. You don't put that stuff on Labs.
(Me, posing as a dog expert.)
Posibly its because we live a lot longer. What was the average life expectancy for most of that evolutionary period? 35 years? I didn't get seriously overwight until my 50's.
"Sirtuins are active during times of stress, including when a person is hungry, and are thought to be related to the known life-prolonging effects of very-low-calorie diets."
I thought that whole low calorie/longer lifespan thing was debunked some time ago.
That being said, one needs to be careful about the cold. I know that if you go too cold that can cause a kind of hibernation-mode which is counter-productive.
Personally, I think it's an Enviro-whacko scam to get people to turn their heat down.
Ann Althouse said...
"Then maybe you shoud knit something for the dog. And get him some booties too."
"He's a Lab. You don't put that stuff on Labs."
You seemed worried that he'd get frostbite.
I've done (and published) some research on cold and sudden cardiac death and one thing you don't want to do if you're at risk for cardiac problems is make yourself cold.
That said, I'm not entirely sure what they're getting at with this "7 million years of dealing with cold". Our species only moved out of the tropics fairly recently; we're essentially hairless tropical monkeys.
Edmund: Yeah, scuba is great for losing weight. I'd usually go from 155 to 150 over a week on a dive boat, even in quite warm water, and eating like mad. (Oh boy do I remember the Peter Hughes trip where the fleet chef was on board. Yum.)
Re: swimming and weight loss - not sure about LOSS exactly, but the best shape I've ever been in overall was when I was swimming 2-3 lunchtimes per week, maybe 2500 meters each. (Of course, not having time to eat probably helped.) Swimmers in training or serious workout SWEAT pretty freely in the pool, even when the water is moderately cool. Being chilled was never a thing.
I have Type I (insulin-dependent) diabetes, and I require more insulin during winter months.
My doctors profess unfamiliarity with such a seasonal change.
Michelle Dulak Thomson: WTF? Most of humanity isn't too cold; it's too hot. Please, look at what fraction of the global population is between the tropic of Cancer and the tropic of Capricorn, and get back to me.
Anthony: That said, I'm not entirely sure what they're getting at with this "7 million years of dealing with cold". Our species only moved out of the tropics fairly recently...
This was my first thought, too. Some human populations have cold adaptations (from a lot more recently than x million years ago). Are they more prone to obesity in modern environments than people whose ancestors never left the tropics? I doubt it. (One of my kids mentioned that even the recent stereotypically thin Somali immigrants in her chilly North American metropolis are already starting to pork out. Not getting enough of those bitter Mogadishu winters anymore, I guess.)
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