Imagine you plant Sequoia tree (one of the tallest trees) and other trees in a plot which has the same type of soil (same environment). After a few years, you see the sequoia tree taller than others. Are you going to say the difference in tallness of the trees is because of the soil (environment) or simply because it is the sequoia tree (genetics)? Almost 99% percent of people would simply say it is the sequoia tree. We are not going to sit and argue if it weren't for the soil the tree wouldn't be this tall. But when it comes to obesity, we just can't see the obvious.
2. Just like other genetics disorders, obesity will not manifest if there is no environment.
“Every genetic disorder is 100% genes and 100% environment”, by Ken Rothman (one of the epidemiological greats). A classic example quoted is the phenylketonuria (PKU), a genetic disorder which characterized by a mutation in the gene for enzyme rendering it nonfunctional; this is about as 100% genetic as a disease can get! If it goes untreated, the kids develop mental retardation and brain damage. Nevertheless if there was no phenylalanine given - a phenylalanine free-diet, there would be no PKU, so one could argue it is 100% environmentally determined.
The huge mistake in comparing PKU (or other genetics diseases) and obesity is that in PhenylKetone Urea (PKU) kids are not “hungry” for phenylalanine.
In obesity, hunger is THE fundamental problem. We used to believe that people became fat because they had a slow metabolism or they spent less energy (Non-exercise activity thermogenisis). Now we clearly know that Leptin, Ghrelin and all other staggering complex of hormones are working at the hypothalamus by increasing or decreasing appetite. When leptin deficient kids who have a voracious appetite are treated with leptin, the first thing to drop is their hunger. Kids with Prader-willi syndrome eat from garbage cans because they feel they will die if they don't eat. Bariatric surgery works so well because it is bunting their appetite for some weird reason. People who lose a lot of weight gain weight back because they are primarily hungry.
So obesity is not a “passive” genetic problem where the genes are just sitting there in the background silently until they see food. People eat because they are hungry.
Most obese people are often depressed, lack self esteem and live a life in an endless cycle of self-blaming. There is no other population that has been discriminated for so long, even in the 21st century. These people have been discriminated and judged everywhere, in schools, workplaces, and even by health care professionals. It is clear in research that even health professionals (also people who treat obesity) associate obese people with being “bad” and “lazy” and “worthless”. This is largely because we still think obesity is all about a personal choices and we are too cuddled up in our cognitive biases to question our assumptions.
And for all the normal people who are crying out loud, why can’t you all get a six pack? After all just like losing weight, getting a six pack is as simple eating less and working more.
9. So you are saying just lose 10-15 lbs or 5-7% of the weight?
Losing weight is extremely simple in principle, but extremely hard for the majority and maybe almost impossible for some. And this is what the research says too. IOM (Institute of Medicine) and the NHLBI (National Heart, Lung, Blood Institute) recommends this too. In fact “success” in weight loss treatments is a weight loss of >=5% of bodyweight maintained for 1 or more years.
This amount of weight loss will not bring many people even close to normal BMI. Then why it is set so conservatively? Because we know that majority of people regain almost all the weight back within 3-5 years. The IOM summarized the long term findings by saying” those who complete weight loss programs lose approximately 10% of the body weight, only to regain two thirds back within a year and almost all of it back within 5 years”. And this hasn't changed a bit even now.
We have number of studies to show that even moderate looses have significant health benefits. In fact, two of the the large multicenter trials - the DPP and the LOOK AHEAD study- has shown this.
So lose 10-15 and maintain it for 6 months. If it can be maintained without extreme difficulty, try to lose more. I am not going to sit and argue with people who want to lose more. But they should understand what they are dealing with and be better prepared.
9. People could become fatalistic in their approach to weight loss upon reading the article.
Does anyone here have a better option?
What are you goona to tell them when they fail? And most will. That since it not genetics, it is probably you; so try again. And you thoroughly deserve all the mental agony and suffering you go through and also the stigma associated with obesity?
10. Ok agreed it is largely genetics. It will not change the treatment of obesity since we cannot change genes.
Finally, everything comes down what we can do about it. I wouldn't have written this series if there were no practical applications. Just understanding the biological basis of obesity, changes everything: It changes the way we treat obesity and treat obese people.
| Sun January 29, 2012
It is interesting to also look at those people who win weight loss competitions. I saw what was an advertisement at one cafe, where a woman lost something like 27 kilos in 20 something weeks.
Why doesn’t everyone lose the same amount of weight? I know people will say compliance but there must be some studies where people were monitored.
| Sun January 29, 2012
Really great article - you really stirred up the hornet’s nest with these series though, lol.
You really changed my view on this - I was skeptical at first but the physiology is sound.
As someone who used to be obese but has kept it off for 2 and a half years, I have a question:
Because we are biologically driven to be hungry and be obese, does that mean former obese persons who have successfully lost and maintained the weight have an atypical amount of willpower?
Ie, enough of a psychological drive to overcome their biological one?
I’m not at all calling obese people weak-willed at all, just commenting that it takes an abnormal amount of motivation to push them forward - perhaps that is something fitness should be more involved in? God knows the personal trainers I’ve met have been unsupportive. I’m starting to talk out of my ass at this point, but I suppose what i’m suggesting is more of an emphasis on the psychology of dieting in the industry?
I know personally (from my own n=1 experiment) that I would not have been able to lose or keep off the weight as long as I have if I had not committed myself to counting cals and macros and keeping track of my training, every day of the week. Alot of people would call this unsustainable behavior, but it comes pretty natural to me.
| Mon January 30, 2012
I really have to say this series of articles have been enlightening. Keep up the great work.
| Mon January 30, 2012
what if all the trees suddenly started growing again, both the short and tall ones, with the tall one growing more than the short ones. What changed, genes, or environment?
Anoop | Tue January 31, 2012
Thanks for the comment.
Some do find it easy to lose a lot of weight. While some find it hard. And hard to say looking at one or two cases. Most before-after pictures, people intentionally put a lot of weight, and then lose it. So it looks like a lot of weight in a short time.
Thanks! It is great to hear that I changed the way a few people think about obesity. I hope you watched the Friedman presentation.
Finally it comes down to a battle of conscious motivation versus the unconscious biological drive to eat and gain the weight back. Some people might have high leptin sensitivity or lower leptin resistance and some just have higher motivation levels and some may have both or some other unknown factors. This is the same way how leptin could help some lose weight, while it doesn’t work for the majority. This could also be why weight loss drugs are ineffective in some. So there are clearly biological changes that help some lose weight and maintain without any fuss. And it also depend on how much weight you lose too. 10-20lbs weight loss is maintainable. But the further you move away from this range, the harder it becomes.
And it is a good point. We might be focusing too much on the carbs, fructose, and minor details while we should be focusing on the psychological aspects . And recent studies are showing that it doesn’t matter what diet you are on and we should focus more on the behavioral aspects. Keep in mind, cognitive-behavioral approaches play a big role in weight management. So it is not that we haven’t focused on those for the past 40 years.
Thanks Denis for the comment.
Sure it is environment if they grow taller. It is just like the 10-15 lbs gain due to the environment. When people are 150-400lbs, the 10-15 gain doesn’t really add up to much. The relative differences are still huge. The lean will stay lean and the heavy will stay heavy. The same could be said about height. We have increased by an inch in the last couple of decades. That wouldn’t make us say height is largely environmental right.
| Sat February 04, 2012
Just wanted to drop a line and say how much I appreciate your thoughtful, patient, science-driven approach in all of your articles.
Anoop | Sun February 05, 2012
That was really kind of you to take the time to say a good word.
| Mon February 06, 2012
I totally agree that we should emphasize more on the psychological aspect of dieting than discussing details like eating carbs at night or doing cardio fasted.
| Mon February 06, 2012
It is incorrect to say that an extreme hypo-caloric environment (e.g. concentration camps) constitutes “no” environment. By that logic, an equally extreme hyper-caloric environment where hyper-palatable food is abundant and free (e.g. someone who owns a candy store) is also “no” environment.
Clearly, food environments exist on a gradient; they are not a bifurcated between “no” environment and “some” environment.
Of course, the concentration camp example is extreme; it is not designed to illuminate free living conditions. It is merely designed to show that the genetic influence on fat gain is limited, and in fact regulated, by the food environment. In a hypo-caloric environment (e.g. camps) everyone is lean; in a moderate food environment (e.g. agrarian pre-Industrial) most people are lean, but a few are fat; in a hyper-caloric food environment (e.g. Kings and Queens of England in the middle ages, the North American diet etc.) some people are lean, many people are overweight, and a minority of people are obese.
The change in the food environment is concomitant with the change in population fatness; that’s what we mean when we say that the obesogenic environent has ‘caused’ the obesity epidemic. We don’t mean that every contributing factor is environmental, nor do we deny the necessary permissive role of genetics; we simple mean that the change in environment explains the concurrent change in population fatness.
Now, it seems we all agree on the substance of the issue (i.e. that people have gotten fatter and that it is the change in the food environment that explains this change). The only disagreements are on the semantics (i.e. what constitutes a ‘cause’) and on the magnitude of the change in population fatness.
Personally, I’m happy to agree to disagree on those two issues. I think causative factors are better understood as regulating, rather than permissive factors. And I think that the population’s mean body fat percentage has dramatically worsened over the last 30 years….even if that doesn’t show up as a huge increase in mean BMI change.
P.S. The ‘obesogenic environment’ hypothesis(which subsumes the food reward hypothesis) does not blame obese people for getting fat. Nor does it deny the importance of weight loss maintenance. Nor is it incompatible with empathy and compassion…etc. It is not a case of “either we accept that genetics controls body fatness or we treat obese people like moral failures”...; it is possible to realise that environmental forces cause population fatness, and that both personal and social changes need to happen to combat this problem effectively.
P.S.S The tree analogy is a disanalogy, due to the use of different species (i.e. you’re introducing a confounding variable). In human, people with the SAME genetic heritage are either lean or fat, depending on food environment (e.g. native Okinawans versus those that emigrated to the US mainland). To make your analogy sound, you would have to plant the SAME trees in different nutrient environments and observe the differences in growth.
Anoop | Tue February 07, 2012
It could be true. We probably are focusing on the wrong side of the coin. And research is showing the same too.
I think you are missing the point. We all agree on the change in environement is making people fatter. What I am saying is that 5-20 lbs increase in fat is not what making people obese . Unless you say people are gaining 40-100lbs due to environment, it is just not really adding much to argue about. The same people who are obese now will be just less obese in a pre-agrarian society. This is the same reason why there were obese people 2000 years back too. The environment is just pushing people who are right below the 30 BMI category to over 30 and classifying them to be obese. .
I don’t understand your comments about the tree analogy. The analogy was just to show that that anyone could easily go round and round to say that if it weren’t for the rich soil the Sequia wouldn’t have grown this tall. And they would be technically right. But most people simply don’t.
| Sun February 26, 2012
As a trainer, given that the substantial majority of my trainees are weight-loss aspirants, I appreciate the circumspect tenor of your article. It ain’t easy. And I readily confess that I can’t help everyone who comes to me.
That said, I’m slightly more optimistic perhaps than you are. Foolishly so ? Time will tell.
Part of my optimism stems from the fact that weight-loss aspirants are almost always people who lost weight previously, often gobs of it ... and gained it back. And when I ask them why they think they gained the weight back, without hesitation they *always* say something like “Because I went back to eating the way I did that made me fat it the first place.”
Given that that is always the case, as a trainer, I ascribe importance to the environmental/genetic factors you underscore only insofar as I am inclined to be more sympathetic towards some than towards others. In other words, I realize full well that it may be more difficult for some than others to cultivate the enjoyment of smaller amounts of food, it’s obviously something that can be done.
Also, I do speak to people, on a fairly regular basis, who attest that, having taken the weight off, they no longer suffer the sort of malignant attraction to food as they did while obese. Whether this is psychological or an actual hormonal change, I wonder if it really makes any difference.
Oh, and a special shout-out to your observation about dramatic health improvements with marginal weight loss. I do see that time and again with my trainees. And betcha by golly we celebrate that, as an important milestone, on the way to greater weight loss.
Currently, I’m working with a diabetic who aims to lose 100 pounds. But after losing the first 20 her A1C has dropped from 13 to 9 (nearing normal) and her average blood sugar levels, just weeks ago alarmingly high, are normal. This phenomenon is BY FAR one of the most rewarding aspects of my job and it sometimes perceived as an unexpected bonus by people I work with who want to lose large amounts of weight.
| Wed February 29, 2012
Well, there are a lot of tree-species that develop very differently due to their environment so I don’t see the need to use different species, in regard to your response to Harry.
However, with regard to our rather heated exchange earlier, I do see your point now and I think you have provided a bascially sound argument for it.
Also, I do wholeheartedly agree with your conclusion that we need to stop stigmatizing fat people.
| Mon March 12, 2012
Haven’t been here in some time, which I feel I must apologize for, since supporting your extremely professional approach to health and fitness must be done at all costs.
I just watched this today about obesity, and immediately afterwards thought of your site.
Low and behold, you just did an article on obesity.
Here is the video:
Anoop | Sat March 17, 2012
It is not being optimistic and such. We have to go by what the numbers say. We have lot of cognitive biases which leads us to wrong conclusions.
The hallmark of science is skeptical thinking. So I always welcome counter points. Sometimes I get caught up in a cognitive bias too. Thanks for the discussions.
Hi The Dane,
Thanks for the kind words, Dane.
| Sat March 17, 2012
I’m not sure what “cognitive biases which leads us to wrong conclusions” means. Do I wrongly conclude that people become obese due in large part to overeating, lose weight through calorie deficit, and then regain weight by returning to old eating habits a wrong conclusion ?
I don’t think so.
Anoop | Sun March 18, 2012
I am just saying why you and everyone just cannot agree that weight loss and maintenance is extremely hard for many, though the research clearly shows it.
Basically because your conclusions are based on a few anecdotes you see and hence those incidents leave a lasting impression on you. Yours is just like everyone who see people lose a lot of weight which makes a dramatic impression. And every time you talk about weight loss, you immediately think of these instances and form a quick conclusion ( since they are readily available).
Hence the reason we should look what the research says about weight loss success, which is pretty pathetic. Here personal experiences are influencing more than statistical information.
This is called the availability bias or heuristic. One of the many cognitive biases which lead us in the wrong direction.
| Sun March 18, 2012
Alright, you can spare us the Latin and Greek. Yes, the studies are in ... and they show that: (1) some are more apt to be obese than others (2) it is more difficult for some than others to lose weight and (3) some are more apt to regain lost weight than others.
Seriously, who knew ?
Tell you what, I’ll be sure and let you know the first time an obese, prospective client offers to pay me to take 5-7% off their bodyweight so they can normalize their health markers.
5-7% is the zone they typically rocket past on their way to more significant weight loss. Are you seriously going to suggest that the world would be a better place if I told my clients to cool their jets ?
BTW, this is not an heuristic. This is sarcasm.
Anoop | Sun March 18, 2012
Read the conclusion again. If you can maintain it for 6 months, lose more. That’s not me. Those are the guidelines and there is a good reason they are set.
And if you lose 1-2 lbs per week, they wouldn’t “rocket past”. If they are, they are losing muscle too.
That’s one reason they “rocket back” to their previous weight.
| Sun March 18, 2012
Whose guidelines are we talking about ? Are these some of the same people who told us that eating fat was making us fat ?
Quite typically obese people will lose 10-15 pounds the first week! Telling obese people to lose a comparative handful of pounds and then having them hold is, in my view, akin to watching a baby take his first few steps and then confining to the stroller.
When obese people begin to cultivate a healthier relationship with food ... good luck trying to keep the weight on them!
I do not grant this necessary correlation between rapid weight loss and rapid rebound. Indeed, one new study showed that people who lost 10% of their bodyweight rapidly were more successful maintaining than those who lost weight gradually.
I also suspect that fear of muscle loss is overstated so long as one is strength training.
Anoop | Wed March 21, 2012
These are the federal guidelines from NHLBI proposed in 1998. They will be updating these in 2012, but I don’t see any major changes.
All that talk about cultivate a “healthier relationship” just sounds great in theory.There are lot of obese people who eat healthy and exercise, but are still struggling.
And that’s a good point. VLCD is an effective diet. But now studies have shown taking a slower route maybe better.Large part of the reason is it is easier to make lifestyle changes and stick to it if done gradually.But either way we are not really getting there.
The whole keep muscle mass when dieting is just a sound theory.I don’t think we have any study to show that people who weight trained kept off the weight longer. We trainers like to talk about it because that is what we mainly do with our clients! But it is still an upcoming area in obesity field and not studied well.
| Fri March 23, 2012
Great Series Anoop! I had a long wait at the supermarket checkout last night and couldn’t help but notice what people had in their grocery carts. The two that stood out were older women of different nationalities that were in good shape for their age. The were probably older than they appeared. Both had their carts filled with fresh vegetables, fruits, and the chicken breast that was the feature special ($0.89/lb) this week.
I then noticed some other people in line with over-weight appearances with their cards full of convenience foods, chips, desserts, and pre-fried oven bake foods (also on special this week).
These comments are strictly on the peoples appearance. It would be interesting to see a study of random grocery shoppers to see how they would do in a fit test and maybe see some simple blood work results then compare it to their diet based on their grocery purchases.
Anoop | Sun March 25, 2012
And that might be the problem. They just cannot control their food behaviors which maybe driven by their genetics.
The same reasoning applies for obese people eating more. But what is making them eat more than us is the million dollar question.
And people eating chicken breasts are just the minority like us. It is not a normal way to eat for the most.
| Wed January 16, 2013
Hope it’s not to late to pose another question. We know that the US has the highest obesity rate of the high-income nations, much higher than most. Accordingly, wouldn’t cultural attitudes towards eating be part-and-parcel of environment ?
America: give 315-million people ready access to food and apparently 30% will manifest obesity.
France: give the French free access to food ... and only about a third of the French will manifest obesity, presumably because it is deeply ingrained in culture to savor smaller amounts of food. What else could explain the disparity ?
Larger question: If there are fewer strictures in America against gorging, how do we know the so-called setpoint, that 10-15 pound range you talk about ? I know a gentleman who ballooned to 525 lbs. Now, I don’t expect him to become a svelte, 185-pounder, but surely he’s not consigned to bouncing around between 510 and 525 interminably, is he ?
Appreciate your thoughts ...
Anoop | Sat January 26, 2013
Never too late for any questions in Exercise Biology!
I don’t disagree. The weight gained due to environment could be due to cultural factors and such. But that is regulated by your set-point. If you think about it, most people look the same throughout their life (skinny 1s always skinny, chubby is always chubby,..). Also, even in the obesegenic environment there are people who are lean with no exercise or diet and whatsoever. If you have to go from overweight to obese, you have to gain around 40-50 lbs. People don’t accidentally put that much weight you know.
People who do balloon like that (520lb) are exceptions and do have some genetic problems.
| Sat January 26, 2013
Thanks, Anoop -
Yes, I grant that the 500-pounder is an outlier. But I do see people, from time to time who, perhaps due to some sort of traumatic event, begin to overfeed, and appear to gain weight in linear fashion for some time.
I’m talking about adults, like my thirty-year old neighbor, who tells me he gained 55 pounds over the last year after he stopped smoking.
Then there’s a friend of the family who says she gained 100 pounds, over the course of three years, after a troubling marriage.
I suppose my question is, how can such people even begin to estimate their ‘setpoint’ ? In other words, seems that gross overfeeding might have them tens of pounds over their optimal (for them) weight.
For these people, would it perhaps be prudent to steer them away from weight-loss goals and invite them to eat more intuitively (and add movement) in the anticipation that they may eventually ‘settle in’ at a somewhat lower weight ?