Evidence against the idea that obesity is cultural:
1) Its got a strong genetic linkage. Cultural phenomenon don't pass from father to son. Type 2 diabetes has a much stronger genetic component than type 1 diabetes.
2) Obesity dispropotionately affects our county's most ACTIVE populations. Unskilled manual laborers, who burn well upwards of twice the daily calories of even the fittest office worker, have rates of obesity significantly above our white collar population that is sedentary for all but maybe two or three hours a day.
3) Many of our attempts to replace empty calories with either nothing or indegestible substances seem to make things worse, not better. Why does diet soda seem to promote more weight gain not only more than nothing, but even more than regular coke? Why are school children who eat breakfast thinner than those who don't? If its cultural, shouldn't every meal and calorie you skip be a positive, so what's going wrong here?
4) Weight gain in individuals, mapped over years, doesn't fluctuate in the way it should if it was cultural. If you look at the average american's weight gain for most indiviuals there is a simple expnential gain curve (you gain a little more for each interval of time compared to the last) with only mild fluctuations around a curve. This doesn't make sense from a cultural standpoint. If it was a meme, and not an biological phenomenon, you would expect massive variations in rate that people gained weight, with years of weight LOSS ('fell in with a healthy crowd'), occasional 50 lb a month weight gain (went on a bender), and periods of keeping your weight flat. People who lose 100 lbs should be any more susceptibe to gaining it back than a thin person is to gaining it in the first place. Older people shouldn't be more likely to gain weight than younger people. But that's not what we see. The constant weight creep we actually see, and the tendancy of people to return to their previous set points even after losing large amount of weight on crash diets, strongly suggests that this is a physiologic rather than an endocrine phenomenon.
In every generation there is a medical phenomonen where a particularly epidemic, hard to understand disease gets labeled a lifestyle problem rather than a medical problem. And we promote absolutely useless lifestyle changes to cure it until someone comes up with an actual cure, at which point we shake our heads sadly at how stupidly everyone else was acting. Before WWI it was TB: exercise more, exercise less, move to a dry climate, eat this, don't eat that. The central message of our treatment was that it wasn't so much an infection as a lifestyle choice. Then we discovered isoniazid and it became just another infection again. For our parents generation it was ulcers. Remember when people used to talk about how stress, or inactivity, or whatever would 'give you an ulcer'? People still say that! Then we found out that it was actually the fault of H-pylori, we discovered triple therapy, and ulcers went back to being a medical problem and not a psychiatric one. Now we have a massive disorder of the nation's endocrine system: people are gaining lots of weight. Something is clearly wrong with the system by which we regulate our hunger drive and metabolic rate, and something is disordering it. Is it a subset of the foods we eat (taube's theory)? A chemical we consume? An infecion we don't know about? A side effect of a medical therapy? I'm not sure, but the evidence is overwhelming that this is more than us getting lazier. And when someone figures it out and cures it y'all gonna be embarassed.
1). I agree there is a genetic component (for some people), but I don't think it explains such high rates of obesity overall. Sure, people with thyroid issues or abnormal neural networks in charge of hunger may have problems with obesity, but things like this are not accounting for a 35% obesity rate. And to say cultural phenomena don't pass from father to son is a bit misleading. They don't pass physically or genetically, but they do get passed down through experience. They've done surveys of kids political/religious affiliations at various ages - many simply mimic their parents and there are only deviations at older ages. Eating habits get passed down too. Hell, parents are responsible for almost every meal a child consumers for many years of their life. You're going to tell me that a parent who decides to feed their kid Chef boyardee and McDonalds every day is getting fat because of genetics?
2) Unskilled manual laborers are in a poorer socioeconomic class. When you are poorer, you buy cheaper, less healthy food. Just because they burn twice as many calories a day doesn't mean they are running a caloric deficit. Hell, I can burn 400 calories on a run, but if I come home energized and starving and eat a piece of cake, that last half hour of exercise is moot. If you show me an unskilled manual laborer and an office worker who eat the same amount of calories every day and the unskilled laborer is still obese, then I'll concede that genetics is the issue.
3) Think about this a little more in depth. Who drinks diet soda? People watching their weight. People who understand nutrition will drink a regular soda, but also have a moderate portion size. It's not guaranteed people drinking a diet soda will do that. Once again, compare a diet soda drinker and a regular soda drinker who have the same caloric in take. If there diet soda drinker is still obese, then I'll concede that biochemistry and chemicals are the culprit.
Your breakfast idea is kind of weird, unless you're telling me that periods of starvation are good for your metabolism. I'm fairly certain research shows skipping meals isn't good for weight loss, but you can correct me otherwise. Obviously this indicates there is more at play than simple caloric balance, but that doesn't negate the effects of sedentary lifestyles and general poor health habits.
4) As people get older, they have less activity and a slower metabolism. Is there something I'm missing? I know about set point theory, but just because it exists doesn't mean you can't break it. You just have to work harder to get past it.
I used to be 65 lbs overweight (obese). I lost 45 lbs over two years simply by eating less. Whereas I used to get McDonalds late night coming home from somewhere, I don't anymore. I used to have a few cookies after every meal. Now I have a small dessert only at night. I used to drink a lot of lemonade with my meals, now I don't. Then I started exercising and after a year, lost an additional 20 lbs. Celebrities speak of doing this. I've had a fat friend or two show similar results after beginning to take exercise classes. Are you going to tell me that it's our genetics that allowed us to lose weight?
Bangers, let's say for the sake of argument you are right and fast food consumption is increasing. If this is true then why are the two year outcomes for dieting so poor? One would think that once people understand what you consider a healthy and unhealthy diet then it would be corrected and the problem would be solved-yet it is not. And what about the fat loss plateau, even if people stay above 700 kcal/day it still kicks in, so what's up with that? This makes me think that there is more going on than simply increased access too fast food.
Regarding the animals, I just wanted to show that activity levels don't dictate weight in other species but physiological need does. If people are storing lots of saturated and vegetable oil fats then there are physiological reasons for this. If they have trouble losing them (most dieter-exercisers plateau at 10% of weight can't lose any more weight after this). There is probably a physiological reason for this.
I never claimed fast food consumption is increasing. I simply stated that healthier food products have increased in price faster than unhealthy food products. I'm not trying to make proven claims, I'm just simply addressing what I believe are links, backed up by numbers. Disproportionate rates of poor people are obese. Unhealthy food is cheaper than healthy food. Poor people often work many hours and can't prepare healthy dinners. To say poor people have higher rates of obesity because of lifestyle is a little less of stretch to me than saying their genetics is at fault.
Let me ask you a question: Are you absolutely oblivious to the psyche of a dieter? You may be skinny for your whole life, but you've never had an experience/discussion with an overweight friend or individual about their weight? Diets aren't lifestyle changes. They are diets. Two year outcomes are probably poor because people don't stick to diets, even though they have the information. People know the risks of cigarettes but they still smoke. Do you think people can become addicted to eating lots of food? Or are you going to realize that people make choices in life regardless of how they know it affects them. Some just want to enjoy a good piece of cake for the taste. Some like a cigarette to calm down. It defies health logic, but it happens. My grandmother is a binge eating and has periodic ups and downs in weight. She has been to Weight Watches for 30 years with other ladies just like her. They know exactly how to eat properly. Sometimes they choose not to. When they do, they gain weight.
It's been 4 years and I've kept all 65 lbs of my previous weight off. I still don't eat McDonalds, I limit my dessert in take and I exercise 7 days a week. Are you going to say I'm a statistically anomaly or that genetics did it? I didn't just diet; I changed my habits and saw results. Set points and fat plateaus may play a part, but I'd say losing 10% of your body weight is a pretty good start. If all of the people who are 10-15 pounds over the obesity mark lose 10% of their body weight, they suddenly become overweight. If they don't regain any of the weight, maybe at some point they can lose another 10%. Now they are close to average weight if not average already.
You're animal example is ridiculously flawed. Does that mean if a sloth begins eating lots of fruit from trees it won't get fatter because its physiology wants to keep it at it's normal weight? I'd be willing to bet it gains weight because it suddenly ingests a lot more calories than it is used to getting from leaves. Blubber in whales is there for a purpose, but I'm sure whale weight fluctuates from animal to animal based on krill in take or something like that. Afterall, whales can probably starve to death.
Physiological need will dictate our diets to a certain extent. There's no doubt that genetics certainly play a bigger role for some people than others. However, you can't ignore broad cultural changes in search of a genetic fix, much like you can't ignore someone's genetics IF they have tried to lose weight. A dieter who loses 20 pounds and goes back to eating unhealthy things should gain weight again. That's cultural, not genetic. However, a dieter who loses 20 pounds but gains it back on the same diet (an unlikely scenario) probably does have some physiological issue. Look at weight loss success stories. Look at weight loss failures. I'd say a majority of the failures stem from poor habits, rather than an unwilling body.
Finally, I'll say this. A guy studied some indigenous tribe in the Amazon and found that they followed a paleolithic diet that contained about 50 mg of sodium PER DAY. This same man found that strokes, heart disease and high blood pressure were virtually non-existent in the tribe. Can we make definite conclusions? No. Does it mean this tribe has genetic resistance to such disorders? Possibly, although I'm skeptical. Does it mean that high sodium diets seen in the West could contribute to so-called "diseases of luxury?" I tend to think it has at least some effect.
Poor dietary habits (especially the consumption of refined sugars and high GI carbs) and decreasing activity are definitely culprits somewhere along the line, but there is a lot more going on than that. In fact, as someone mentioned earlier, the higher levels of obesity are actually seen amongst the labor class, that is folks who expend a greater proportion of calories on a daily basis.
I posted this already, but watch this. At the very least, it's good food for thought...
http://vimeo.com/45485034
Calories In-Calories Out ("eat less, move more") is an oversimplified, outdated paradigm that rarely lends to long-term practical use. If anything our first semester in medical biochemistry should have highlighted the intricacies of human metabolism and how such an over simplifications can lead to misinterpretation and faulty advice based on such. We should most definitely be investigating such intricacies and deciphering the elaborate interplay in a way that allows us to develop solid dietary advice for those struggling with obesity. Vilifying patients for being lazy and undisciplined is the not the answer, especially when some of the advice they've been given may have missed the mark.
First of all, props on your avatar. One of my favorite movies. Second of all, I don't have the hour to spare, but I'm aware of studies suggesting cholesterol/fat intake doesn't necessarily affect blood cholesterol levels etc.
I'm not denying there isn't a possible genetic component. I'm just saying that culture and habits play large roles for many people. I don't think you're willing to say 100% of obese people today are obese because of genetics. Sure it's harder for some people to lose weight and sure things like underactive thyroids can contribute to the issue, but there are a good proportion of people that eat too much and when (if) they stop eating, they lose weight. I can't put hard numbers on it, but I'd be willing to bet at least half of obese people can fix their problem by changing their habits, rather than their genetics.
As for manual laborers, how do you know for sure workers burning lots of calories are in absolute caloric deficit? More often than not manual laborers are in a poorer socioeconomic class that is prone to eating poorly. Just because they burn off a lot of calories doesn't mean they are in a caloric deficit for certain.
You're right that we can't vilify overweight people. I know from experience how hard it was to lose weight after being heavy for so many years. But that doesn't mean it can't be done because genetics is preventing it.
