Why are we getting fatter? Researchers seek a mysterious culprit

So, why are we fat? And getting fatter? Most people would say it's simple: We eat too much and exercise too little. But University of Alabama at Birmingham obesity researcher David B. Allison, Ph.D., says that answer, while valid, may be a little too simple. Allison and colleagues think the more relevant question is this: Why do we eat too much and expend too little energy? And like good detectives, they've set out to identify a suspect, or suspects, that may be contributing to the obesity epidemic. The game, as they say, is afoot.

Allison, a professor of biostatistics in the UAB School of Public Health, is senior author on a paper to be published Nov. 24, 2010, in the British journal . That paper, provocatively titled "Canaries in the coal mine: A cross-species analysis of the plurality of obesity epidemics," suggests that the root cause of obesity may be much more complicated than the conventional wisdom — too much food availability, too little opportunity to exercise.

Allison's current sleuthing began when he was looking over data on small primates called marmosets from the Wisconsin Non-Human Primate Center. He noted that the population as a whole showed pronounced weight gain over time. Checking with the center, he could find no compelling reason. The nature of the diet had changed, but controlling for the exact date of the change, easily doable with animals living in a controlled laboratory environment, only strengthened the mysterious phenomenon.

Intrigued, he began searching for more evidence. Needing raw data, he tracked down previous studies of mammals, living with or around humans, which had lasted at least a decade. He found information, called data sets, on 12 groups of animals. Divided into male and female populations, he ended up with 24 data sets, containing information on more than 20,000 animals.

The data sets were varied. Some were laboratory research animals — monkeys, chimpanzees and rodents. Some were feral rats caught in the alleys of Baltimore. A veterinary hospital in New Jersey provided records on domestic pets — dogs and cats. There was one constant. All 24 sets had seen overall weight gain in the population over time. Twenty-three of the 24 had seen an increase in the percentage of obese individuals in the group.

"And yet there was no single thread running through all 24 data sets that would explain a gain in weight," says Allison. "The animals in some of the data sets might have had access to richer food, but that was not the case in all data sets. Some of the animals might have become less active, but others would have remained at normal activity levels. Yet, they all showed overall weight gain. The consistency of these findings among animals living in different environments, including some where diet is highly controlled and has been constant for decades, suggests the intriguing possibility that increasing body weight may involve some unidentified or poorly understood factors."

The mystery deepens. What might those factors be? Allison and Yann Klimentidis, Ph.D., a post-doctoral trainee in the School of Public Health and co-author of the paper, say scientists, including many at UAB, are beginning to look at alternative reasons for obesity beyond the usual suspects of increases in food intake, provoked mainly by availability, and decreases in activity level, provoked mainly by labor-saving devices. Here are several candidates for the lineup:

  • Light. Studies have shown that subtle changes in the amount of time spent in light or dark environments changes eating habits. Allison wonders if increased light pollution in our industrial society may play a role.
  • Viruses. Infection with adenovirus-36 is associated with obesity, and the presence of antibodies to AD36 correlates to obesity in humans. Could AD36 or other infectious agents be contributing to obesity in populations?
  • Epigenetics. Genetic modifications brought about by any number of environmental cues such as stress, resource availability, release from predation or climate change.
The bottom line, say the authors, is that obesity is a problem that most likely has many causes and will need many solutions.

"When looking for ways to combat obesity in humans, we need to be more aware of all the possible alternative causes of obesity," said Klimentidis. "If we can find causes for the seen in our animal subjects, we may be better able to apply that to coping with in humans."


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Nov 24, 2010
Quite simple: Humans are the only animal using cars for transportation; hence destroying their environment and bodies at the same time.

Nov 24, 2010
I find the mention of lighting interesting; Just as low light levels affect the brain to make us sleepy, to regulate our 'body clock', it makes sense that this also affects appetite and aspects of our metabolism. Also, to not eat/ not desire to eat in darkness would have been a sensible adaptation/ a choice we no longer need to make. It may be difficult to separate the data, but I would be curious if there is a correlation to shorter sleep duration and weight gain (kind of the opposite way around to what one might intuitively expect).

Nov 24, 2010
It's dark energy, we are expanding with the universe.

Nov 24, 2010
Predators are missing. No predators, no need to run fast and hide. Then the gain in weight is beneficial - more reserves and more strength translate into clear evolutionary advantage.

Nov 24, 2010
Corn syrup and chemical cosh that goes into everything.

Add soya to the mix and you get a ton of gender-bending chemicals into your body, upsetting the way body stores energy.

Children have their DNA altered in the womb with all the pollution and chemicals.

Nov 24, 2010
Back when we were pre-homonid, the most well fed got to mate most often. Slight chubbiness is still seen as a sign of wealth and health in many cultures.

It's hardwired to consume too much in times of plenty in order to survive the lean times. If you don't think about what you're eating and stop when you're not hungry any longer, yoou're going to get fat.

Nov 24, 2010
Boy, would it be ironic if we were all getting fatter because of increased CO2 in the atmosphere.

Nov 24, 2010
I recently started counting calories (about two weeks ago) and I've found some very simple solutions:

Instead of snacking on chips, snack on a banana or apple. I've recently rediscovered that I'm a huge fan of apples. Also, fast food is okay, but two things: Don't stuff your maw full of food; eat a little less. Also, find something besides the french fries. They add an awful lot of calories for being a side dish.

Additionally, I cut out regular pop out of my diet, but only so I can snack more *eyeroll

Combined with the treadmill I'm down about 15 pounds. I do not feel like I'm on a diet. I feel like I've changed very little, to be honest. I'm just paying more attention to the calories and doing some physical activity.

Nov 24, 2010
I couldn't agree with SH more. In fact I remember (it's been a while ago) reading a study that said as hunter gatherers we got by on a lot of the fat stored on us in the wintertime. The first thing our body wants to do is put fat on us.

Eat less, it worked for me...

Nov 24, 2010
I eat french fries, ice cream, butter cream cakes. My body fat is at around 12%, and I have muscle mass.

How can that be? Well I don't eat french fries, etc. all the time. I exercise. I watch how much I eat at other times.

I've had countless people say that I have been blessed with a fast metabolism. I believe I have a slow metabolism. At night I need to bundle up to stay warm. I've calculated my calories per day and they average around 1700-2200 calories even when I heavily exercise.

So when a fat person say's I'm blessed with a fast metabolism and that they have a slow one, I have to watch what I say. I see them consume 2500-3500+ calories and hardly if ever exercise.

The reason I am of normal weight is discipline, and if I eat junk I balance it out. Anyone who wants to be at normal weight, all you need is discipline and balance. Fad diets, operations, excuses, etc. wont help.

Nov 24, 2010
Well, it looks like none of the people who are posting here actually read the story! It reports a finding that exercise and calorie intake are NOT the cause of more obesity. The fact that people can read something and not see it speaks to a kind of paradigm that overcomes reason. People are resistant to scientific change, even if the data tells you that the current theory does not explain the observed facts.

Nov 24, 2010
Predators are missing. No predators, no need to run fast and hide. Then the gain in weight is beneficial - more reserves and more strength translate into clear evolutionary advantage.
People even a few gens were much thinner. I dont recall any fat people in my town growing up.

This epidemic is a recent phenomenon.

Nov 24, 2010
Well, it looks like none of the people who are posting here actually read the story! It reports a finding that exercise and calorie intake are NOT the cause of more obesity. The fact that people can read something and not see it speaks to a kind of paradigm that overcomes reason. People are resistant to scientific change, even if the data tells you that the current theory does not explain the observed facts.
Amen brother. Especially a lot of the posters on this site. Dey loves da party line.

Nov 24, 2010
Well, it looks like none of the people who are posting here actually read the story! It reports a finding that exercise and calorie intake are NOT the cause of more obesity. The fact that people can read something and not see it speaks to a kind of paradigm that overcomes reason. People are resistant to scientific change, even if the data tells you that the current theory does not explain the observed facts.


Anyone, and I mean anyone who says intake has nothing to do with obesity is an idiot. Anyone who can't figure that out for themselves is an idiot too...

Nov 24, 2010
Well, it looks like none of the people who are posting here actually read the story! It reports a finding that exercise and calorie intake are NOT the cause of more obesity. The fact that people can read something and not see it speaks to a kind of paradigm that overcomes reason. People are resistant to scientific change, even if the data tells you that the current theory does not explain the observed facts.


Anyone, and I mean anyone who says intake has nothing to do with obesity is an idiot. Anyone who can't figure that out for themselves is an idiot too...
So you didnt read it either parson? All ya hadda do was quote it:

"suggests that the root cause of obesity may be much more complicated than the conventional wisdom - too much food availability, too little opportunity to exercise."

-He who is without sin throws gallstones; or somesuch.

Nov 24, 2010
In my estimation, the problem is that people don't balance their carbohydrate intake to their activity level. It's possible to not gain weight eating the carbohydrate level of the average American diet, but the level of activity necessary to balance it out is massive. We are far more mechanically efficient than most people realize.
A simple solution is to permanently remove grain from your diet and just eat a piece of fruit with each meal, or more pieces of fruit on days when you are more active. The level of satiety is so much greater that you inadvertently lower your caloric intake and the odds of developing type-2 diabetes are practically nil.
The one downside is that you have to buy a lot of new clothes a couple times. (I'm currently wearing slightly loose-fitting 30-waist Levis 511 "skinny jeans" with size 29 or 28 on the horizon.)
I got here doing no cardio, just body-weight exercises a few times a week for strength. (Deadhang chin-ups went up to 11 from 6 while losing fat)

Nov 24, 2010
Anyone, and I mean anyone who says intake has nothing to do with obesity is an idiot. Anyone who can't figure that out for themselves is an idiot too...


It depends what you mean by intake. I eat alot. Usually three or four meals a day. But I eat home cooked food, lots of salad, and do minimal sugar, have a piece of chocholate once a week. I hardly ever do 2000 kcal a day, and I do exercise.

The result is bmi of 22 and body fat below 10%.

Then again if everyone was healthy and had perfect weight then drug companies would not make so much money.

Nov 24, 2010
ziprar, I agree. Ratfish while some diets are healthier than others, removing grain, bread, or anything won't reduce your weight to normal. Calories in must =< calories out. A researcher just did a report where he lost weight eating only twinkies and other junk foods. If I recall right after 2 months of eating junk food, but less than 1800 calories a day, he lost 20 lbs.

The show biggest loser (though extreme) shows that fat people when combined with a good normal diet, plus a lot of exercise equals health normal weight person after several months.

I would love to go on that show. If I burned as many calories as they did, I would be able to eat more cake, ice cream, and fies than I do now :)

Nov 24, 2010
I still think you cannot eliminate the effects of fluoride in the tap water. Unless these animals were give water that was not from the tap, or unless the area of the primate center is not victimized enough to include fluoride in the tap water (Most certainly I am slanted on this issue), this element of living should not be eliminated from the research.

Fluoride is known to influence the functioning of the pineal gland, which will effect the parathyroid, which would effect the metabolism of the individual, animal or other species.

Do think rationally about it. And don't accept research that is not comprehensive and of good quality. Research releases can sometimes be more propaganda than anything else. But then the above researcher knows that already.

Nov 24, 2010
Another ice age is coming and we are fattening up for it?

Nov 24, 2010
So you didnt read it either parson? All ya hadda do was quote it:

Actually you quoted it badly which led to a misleading conclusion. It's right in the headine:
Most people would say it's simple: We eat too much and exercise too little. But University of Alabama at Birmingham obesity researcher David B. Allison, Ph.D., says that answer, >>while valid
Oink? Arf??

Nov 24, 2010
freethinking-While it's obviously true that you _can_ lose weight by any number of drastic measures, such as those portrayed on that television show, it has been repeatedly proven that such approaches are unhealthy and unsustainable.
Depending upon one's ancestry, we've only been eating grain for some 10,000 years at most, which has simply not been long enough to adapt to it. With the level of sedentary habits that most people now have, the easiest solution is to simply eat in a way more in keeping with our evolutionary design, which certainly precludes massive amounts of grain.
As I stated, you end up lowering your caloric intake without feeling as though you are restricting your diet at all. Good luck trying to gain weight or even maintain a fat surplus eating meat, vegetables and a piece of fruit every meal.
Americans spend 50 billion a year on magic pills, potions, devices and other scams. They just need to not eat grain. Knock the bottom off the food pyramid.

Nov 24, 2010
Yeah, grasses are about the last choice for hunter gatherers because they provide the least return per effort. But they were often the only choice in overcrowded regions. They did grow quickly in soils replenished by seasonal river floods, and so lent themselves to cultivation and later irrigation.

The people who lived on them were chronically undernourished and thus undersized compared to their highland neighbors. Their settlements became the targets of Marauders who found them easier prey than the typical wild game, which resulted in ballustrated and walled villages. This was the state of peoples in much of north America when Columbus arrived.

Nov 24, 2010
The thread of this discussion pretty much says the same thing. Yes, it's likely environment has an effect on us. Though reality check (ref the twinky study) is that calories are all that matter. Ok, so you are toxic, well you need to drink more water and work to cut some of the calories best you can, while adding more fruit in place of the pretzels, fries, etc.

Answer is simple:
1. keep a water bottle nearby and drink your water.
2. add fruit to your lunch and review what's in your cupboard (seriously the answer is there...).
3. try to integrate more excrcise into your day and if not then look for dinner replacements lower on carbs.

"Eat like a king in the morning, a prince in the afternoon and a pauper at night"

Nov 24, 2010
Anybody else got a huge AD for a burger at the end of the article? lol Found that funny.

Nov 25, 2010
Why do we eat too much and expend too little energy?

Maybe we have too many genes in common with pigs. Physiologically pigs are closer to humans than mice(researches into xenno-transplants of pig organs, etc). I'd say most modern humans' level of physical activities is the same with pig (eating alot, not spending lots of energy getting around, almost never run). And, back in Asia, I have seen pigs that didn't get fed enough becoming quite skinny too...

Nov 25, 2010
Fascinating to hear that animals are showing an obesity epidemic, too. Endocrine disruptors seem like an obvious culprit. I've read that they're in the water everywhere at this point, so wild, feral, lab, and pet animals would all be getting dosed, just as we humans are. Endocrine disruptors affect cells via epigenetics, so maybe the researchers are looking at them as a subset of that category? I'll have to hunt for the article to see what they say.

Nov 26, 2010
While I agree the biggest loser is extreme. I have no information that it is unhealthy. I am shocked that no one has died on the show, but the fact that no one has shows that the method is not unhealthy.

taka's hypothesis about less preditors allowing animals around people to gain weight seems plausable. The use of artificial lights also could be a factor.

I will continue to believe that any healthy diet + exercise + moderation = normal weight.

Blaming the environment only leads to more overweight people as it gives people the excuse that its not their lack of exercise or discipline or them overeating that is making them fat.

Nov 27, 2010
This whole article is stupid. If you want to help people, study why they are hungry, not what makes them fat! I've had a couple epsisodes of prolonged gastritis. Guess what? When I wasn't hungry I shed pounds easy. I would actually have to THINK about eating to maintain my weight. Normally, however, it seems I'm hungry constantly.


Carbohydrates are the enemy of satiety. Consider cutting out grain permanently and be astounded by how many hours you get out of a meal.

Nov 27, 2010
Marjon, don't eat Chinese. bad for you and as Mr. Burns pointed out " Those people are all gristle."

Nov 28, 2010
Two culprits: fructose and high glycemic carbs. The latter spikes blood sugar, which triggers an insulin response, which leads to a sugar crash, which diverts chemical energy into fat storage instead of physical energy. Thus a person feels lethargic while all those calories are busily being crammed into the fatty areas. People think it's normal to feel tired after a meal, or crash after a box of doughnuts, but every crash is a step closer to Type II diabetes. Meanwhile fructose can only be processed by the liver at a certain rate and anything extra is easily converted into visceral fat, and enough of that leads to fatty liver disease.

Nov 28, 2010
The FDA food pyramid is turning Americans into a nation of morbid fatties with its recommendation of 5-6 servings of carbs. Even whole grain carbs aren't that good in "normal" portions because they provide very little nutrition for the calories, thus the body feels hungry from malnutrition despite meeting its calorie requirement, and continues eating more, hence obesity.

The solution is to eat more veggies, healthy fats like olive oil, coconut oil, and butter, unprocessed proteins, and whole fresh fruits ... and to reduce carbs to 1/2 or 1/4 portions. It's worked for me.

Nov 28, 2010
I bet a candy bar that the researchers are overweight.

Nov 28, 2010
@freethinking: while eating crap and restricting calories can result in weight loss, you will still not be getting proper nutrition nor does that sound realistically sustainable for life.

When you eat the right foods (lots of good meat protein, fats, and not carbohydrates from grains) you can actually eat above your caloric maintenence and still not gain fat.

You can also eat crap and exercise it all off, aka the treadmill cycle, but again this is not the healthy option.

It takes very little exercise to maintain a healthy body weight when you are eating properly and not getting the majority of your caloric intake from quick-digesting, insulin spiking, glycogen creating carbohydrates.

Getting in shape and being healthy for life is 80% diet and nutrition, and 20% exercise.

Nov 28, 2010
Before anyone thinks I advocate eating junk food all the time, I don't. I limit the amount of pop I drink as well as my kids (They can only drink 1/2 cans, if we eat out and can fill the cups, I fill the cups full with ice). My kids and I all love vegetables, and rather have that than junk.

All I was saying is that people worry too much about the food, but not the quantity of food. They try and limit one type or another, etc.

Unless there is medical reason, all food is ok in moderation. Exercise is also good.

BTW My % body fat is 12%. I can run a mile in 6:30, and can bench press over my weight. I am in better shape than most Americans.


Nov 29, 2010
What absolute PURE bovine feces this is. People are getting fatter, particularly Americans, because they've been poisoned for 30 years on the "balanced diet" BS fed to the public by the ADA and FDA.

Increased sugar and carbohydrate-laden foods in our diets over the past 50 years, along with less activity, is the true culprit. You ARE what you eat. Walk through a Walmart one day and look around. Everyone is fat. Why? Because the cheapest foods, the ones that the poor and middle class live on, are also the worse ones to be eating when it comes to caloric and carbohydrate content.

Which brings us to the epidemic of Type 2 diabetes now occurring in the U.S. Why is that happening? Same reason; sugar and carbohydrate-laden foods. The above talk of viruses and other causes of obesity, while true in some instances, are definitely NOT the causation for 99% of America's fat.

Nov 29, 2010
The solution is to eat more veggies, healthy fats like olive oil, coconut oil, and butter, unprocessed proteins, and whole fresh fruits ... and to reduce carbs to 1/2 or 1/4 portions. It's worked for me.


So true. They started a war against dietary fat in the 70s and heavily promoted grain and look where it got us. I eat butter, chicken dark meat with skin, whole fat cheese etc., vegetables and a piece of fruit for each meal and I am sated for hours and hours and continue to lose fat. Currently 5'10" 143 and I just did a set of 13 deadhang chinups a minute ago that a drill sergeant would approve of. I wish I had done this years ago.
For Thanksgiving, I only ate a ton of turkey, a reasonable serving of sweet potatoes with butter and asparagus. Everyone else was hungry a few hours later but I had no hunger 8+ hours later.

Nov 29, 2010
What did I eat for thanksgiving? White meat no skin turkey, I don't like dark. Sweet potatos, beans, pumkin pie (no crust, I don't like the crust) with whipped cream, a bit of stuffing (not a big fan of stuffing), cranberries, a couple of salads, and mashed potatoes made from skim milk, low fat sour cream, cheese, and butter.

Over 4 days of leftovers. I gained no weight. I do 100 tuckups, 50 pushups, 100 leg raises, assorted other core exercises, 5 minutes of jumping, and upper body weight training 5 days a week.

Resting pulse 52,BP - Normal, LDL 120, HDL 54 Cant remember tri but I believe it was in the 50's. Height 5 10, weight 158lbs.

Balance is whats important. The less processed the better. But if you ate only the healthiest food in excess, you will become fat and sickly.

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