Thursday, January 22, 2009

Genetics Vs Free Will

I make no qualms or hidden behind the fact that I am a scientist, and more specifically a geneticist.

I've studied genetics and learned many techniques for understanding genetic experiments for about 4 years now. We have been researching genetics since the late 19th century when Gregor Mendel was playing with some peas in his backyard.

We were aware of transposons --special sections of DNA that move from one section to the next having an influence on the transcription of a gene and it's expression-- since the 60's. Breeding and artificial selection itself has been going on since we first became an agriculture society oh 12,000 years ago or so.

But there is still this hope, this dream that we can all overcome it. People assume all that genetic stuff in your cells is just an idea and that free will with lots of hard work you can defeat. There are dreams that we can easily rid ourselves of genetically predisposed diseases when in practice even the only disease that is caused by one gene (which is an incredibly rare thing, even hair color is at least three genes), Cystic Fibrosis, one we were sure to cure with gene therapy is alluding us.

Yet people, doctors, the media, and every arm chair dietitian in the world thinks you can completely overcome your genetic code and be as thin as you want just by "eating less."

Someone finally got in their head to do a little study to test this theory --it's so small I can't even call it an experiment-- involving thin people who are told to over eat and under exercise. It's the exact opposite of a diet which we all know, and even WW is claiming now, doesn't work.

There is a reference to an older study that I think people would find very interesting to learn about "In 1967, a medical researcher, Ethan Sims, carried out an experiment at Vermont state prison in the US. He recruited inmates to eat as much as they could to gain 25% of their body weight, in return for early release from prison.

Some of the volunteers could not reach the target however hard they tried, even though they were eating 10,000 calories a day. Sims's conclusion was that for some, obesity is nearly impossible."

People who could have gotten released from prison could not eat their way to obesity, yet people are expected to starve themselves down to a "normal" weight. Perhaps I am missing something here but doesn't that go against every rhetoric we've been fed since some diet company got in bed with the government to create the "Obesity Crisis."

Imagine if instead of pounds we're all being told is the enemy it's inches. Why just by eating this magical pill and standing in a small box for a few hours you could decrease your size in 10 weeks.

There's even a surgery you could do to decrease the size of your leg bones so you'd be as short as you always dreamed.

Seems insane doesn't it? Well height is just as much determined genetically as weight. We can affect it some with hormones but most parents who force their children to take growth hormone to get taller are frowned upon. But what about that parent who signs their child up for lap band surgery or puts them on alli?

For a better take on it all check out this article about the "Tall Epidemic."

Maybe it's all part of the mythical American Dream that we can overcome anything life throws our way and the idea of something as simple as the crap shoot of your parents DNA intermingling causing a greater affect on you than your own will power terrifies us.

And as sad as it is, I know I could spout all the statistics and data til I was blue in the face and still our world perception is that a person just eats themselves into obesity and it's all their lazy ass fault yet a person who is thin and can eat whatever they want should just thank Lady Luck.

Everyone wants to ignore their own little DNA sometimes to disastrous results.


Linda said...

I have been told repeated by docs that I should lose weight and looking at my parents they said it would be tougher for me given my genetic history. Not tougher, impossible. I accept that my DNA makes my hair black and my eyes brown so I also accept that it add 20 lbs to my hips :)
People like to think that they have control over everything. You don't accept it. Make your life a little easier.
Sorry got a little preachy there. Thanks for posting this. Great topic.

Anonymous said...

I agree with you for the most part but I don't believe that every overweight/obese person is genetically predisposed to be that way. Unfortunately there are a lot of people who do eat and laze their way into obesity. We're not meant to be sedentary in nature, however our western culture and society almost forces us to be. (ie. Office jobs, cars, computers, etc.) I personally think it depends on how healthy the person is - if you exercise and eat healthily and watch portions, it doesn't matter what size you are.

(Personally, I think the reason why the prisoners didn't gain any weight is probably because they were expending that amount of calories everyday in labour. My sister's boyfriend is training to be in the Olympics and he eats 12,000 cal/day and is slowly gaining weight but he probably uses most of it when he's training all day. Plus, the guy is all muscle and muscle uses more calories to maintain than fat. So maybe the thing is obese people shouldn't be starving themselves, but instead exercising to build muscle.)

Anonymous said...

Interesting take on weight loss (and gain). Guess I never thought of it in those terms, but you make some very valid points. Thanks for this post and "opening" my mind! :)

valerie said...

I don't think many people can honestly believe that "fat" people can be healthy. I have normal blood pressure, cholesterol, triglycerides, etc, etc. My blood sugar isn't normal, but I'm controlling it well. And boy am I fat. Oh wait, obese (though I get, OMG, you weigh THAT MUCH? No way!! all the time).

Do I think this is a genetic predisposition? Hell yes. Case in point: my mom. She has dieted, exercised herself to death, eaten 800 calories a day for YEARS. She is still 200 pounds. She absolutely can't lose any more weight. My sister, regardless of how much she exercises or not... 180ish pounds. Are they both healthy? Yes. Do the doctors nag them about being "overweight" and "obese." Yes.

So what do they do now? Starve? Sign up to have themselves gutted so they can starve even more?

I don't think most people realize that BMI is an arbitrary number. Weight is an arbitrary number.

Weight/BMI doesn't reveal muscle mass. Bone density.

Weight/BMI doesn't reveal actual health. Thin people can have heart attacks, high cholesterol, diabetes (TYPE II EVEN! omg!), etc.

The "obesity epidemic" is caused by the radical changes made to the healthcare system to discriminate more and more... in cohorts with the government. BMI standards changed recently too, and we (i.e. the media) suddenly freak out because there's a sudden and severe jump in "overweight" and "obese" people.

Obesity IS genetic. Yes, people can be lazy and eat too much. But even thin people can be lazy and eat all the time and NOT GAIN WEIGHT and still be horridly unhealthy. Even if there are overweight/obese people that are lazy and eat all the time, due to their genetic predisposition to gain and carry more weight, they're going to gain MORE weight than previously mentioned thin person.

I'm sorry. I didn't mean to rant for I am preaching to the choir. Amen and hooray to your post. You're more eloquent than I am. I wish more people took the time to research into this government agenda to create a "crisis" where none exists.

AmyJean said...

Ugh... i've asked my doctor to test my for hypothyroidism, pcos, diabetes etc... trying to figure out why i keep gaining and i can't lose... i'm not obese (yet), but i'm not thin... i'm constantly concerned with my weight... and don't remember a day not dieting... i'm learning with age, we really need to find the right foods to stay healthy regardless of weight... b/c obesity is genetic, and we can only control what we can control... so eating bone building foods and foods that are anti-aging (antioxidants, etc) we can do our part... and exercise... even if its casual, is always key. It may not make you thin... but screw thin. i just want to be healthy now and have a healthy state of mind! :)


Leslie said...


Cate Subrosa said...

I agree that there is a genetic element, but that can't be all there is to it. If that's the case, how do we explain the huge and very recent rise in obesity in US and UK (and a few other places) that is unmatched elsewhere in the developed world? Genes don't change that quickly, habits do.

I'm sure our genes have a lot to do with our size, but we still have a lot of control over it too.

Lindsey said...

Very interesting. You are really smart!

Krista said...
This comment has been removed by the author.
Krista said...

Interesting. I accept that we all have "ranges" of weight our naturally likes. I also believe "obesity" is rarely "genetic". How can we explain the increase over the last generation? Obesity is more than one thing. Sure, an extra 20 lbs on my hips, or an extra 20 lbs in one's belly, is something we're predisposed to.

I think most people who are obese either ate too much or had some other underlying diseases (such as depression, thyroid, etc). And I know how hard it is to lose 20 lbs; once you're "obese", imagine how hard it must be to lose 100 or 200 or more. So I don't trivialize how hard it is to lose weight. My brother's obese, and eats fairly healthy now, but it's hard to lose weight when you're so overweight you can barely walk 25 ft. He became obese during a medical condition.

All that being said, even CF, as you say one of the rare "genetic factors" with just one gene to isolate has some genetic variations in where/how it occurs on the chromosome. (At least, that's how I understand that's what research is showing. I don't know/understand the whole thing.) So I agree with your point, which you illustrated through the failed attempts of gene therapy: the study of genetics is complex. Even though we "mapped" the human genome, we still know so little.

Anyway, I digress. Good post, thought provoking! I don't usually read this blog - I usually read you at that "other" blog :)

Rachel said...

Great post!

Yes, I do believe that your genes can predispose you to be a certain body type and within a certain weight range naturally. If it turned out you're an Olympic athlete, you'd probably be thinner and in better shape than you were predisposed to. But, if it turned out that you ate beanie weenies all day and sat around doing nothing, you'd probably be bigger.
I agree that genes make it harder for some to lose weight, and impossible for others to gain weight. But, while some people are bigger because that's their body type (hey, I'll never be a size 6 myself!), you can't have a poor diet and not exercise and then blame it on your genes. That would be my sister in law, who supposedly has "tried" to lose weight. I say "supposedly" because she also considers mac 'n cheese a vegetable! Oh, and I've never EVER seen her exert herself physically. Ever.

But I do know others who might be considered "overweight" by the charts (hey, I am one of them), but who are healthy and happy. I think it's all relative.

But I will agree with Mrs. Subrosa and say that I don't think genes could make you severely obese. You may be predisposed to be bigger, and it may be easier for you to gain weight, but that just means that you need to watch what you eat more than other people may (and I don't mean starve).

It's similar to intelligence. Some people can just coast through school, not having to study much. On the other hand, others people may have to work their butts off studying just to make a B or C. If you're "obese", you may have to work harder at your weight than other "skinnier" people do.

Oh, and as one person who has had hypothyroidism for over 15 years, I don't like it when people use that as an excuse for being obese. I'm not talking a few extra pounds here. Yes, it makes it harder to lose weight and much easier to gain weight (of course, I'm also older now too) - BUT, the fact that I would like to lose a few pounds comes from me eating whatever I wanted since the wedding,and not exercising. It has nothing to do with my thyroid.

;-) Sorry for the super long post! It's just that it's a great topic, and reading all the comments just got me thinking.
(I told you I need friends!!!)

professional daydreamer said...

i love how so many people are arguing with the geneticist over the influence of genetics based on... what? personal opinion? the latest sensationalized pablum once derived from a study of finches reported on the fact that weight fluctuates by a few pounds depending on habit does not mean that weight isn't genetic. genes are the major determining factor. environmental factors can influence their expression. (i would probably be shorter with a poorer childhood diet, despite being having genes for abnormal tallness.) normal diet variations will cause weight fluctuations of a few pounds. this doesn't disprove the prevalence of genetics. it proves that bodies are adaptable within preset limits. genes determine those limits.

the only woman in my family to have been consistently thin was fanatically obsessed with food and thinness and ultimately starved herself to death. literally. my sister and i have also developed eating disorders, although we've mostly recovered and have developed strategies to help avoid relapse. at my absolute thinnest, my bmi was 24.77. my healthy weight range is considered "overweight." when my thyroid went and failed on me, i temporarily became obese. when i went on synthroid, i dropped right back to my usual weight range even before i worked exercise back into my life. depending on how active i am and how i eat, my weight can wander through a 25-pound range. this does not disprove genetics. it proves that my body adapts to circumstances within genetically-circumscribed limits. it takes extraordinary measures -- hypothyroidism, ED-NOS to the point of hair loss -- for my weight to leave those limits. score one for genetics. my goal is to not die, not to look like other people tell me i should.

regarding the prison study and "expending that amount of calories in labor": no. the prison study was ideal for the researchers' purposes because they could measure and control both caloric intake and energy expenditure. with a controlled labor schedule, controlled exercise period, and supremely limited opportunities for additional physical activity within the confines of a locked cell, inmates would have to be obsessively determined to burn off 12,000 calories through incessant motion, and i think that would be noticed. and if they wanted to be released early, what possible reason could they have for going to such extreme lengths?

regarding the apparent rise in obesity rates over the past few decades: how much of that is truly a bad thing, how much of that is due to the changes in fat-stockpiling brought on by artificial diet restriction, and how much of that exists only in numbers? the limits designating who is normal weight, overweight, or obese were lowered in 1998. millions of people became overweight or obese overnight without gaining an ounce. that is one factor mitigating the trend. dieting causes people to become fatter over time. underweight is dangerous and the average body is designed to prevent it by any means possible -- in this case, by storing more fat than it ordinarily would in response to an apparent famine. intentional dieting has only become popular over the past century, since the release of "diet and health, with key to the calories." the more you diet, the fatter you will become when the restrictions slacken. if you want to avoid becoming fatter than necessary, don't starve yourself. and finally, isn't fat, on a global scale, considered a good thing because starvation is bad? what is the rate of malnutrition like now in north america compared to previous centuries? i think access to adequate nutrition, period, has had an impact. easy access to food, including the highly-processed convenient stuff many people favor, means you are more likely to be at the upper end of your natural weight range than at the lower end, and that perhaps some vulnerable people are more likely to be supersized instead of merely obese. this doesn't seem particularly alarming.

people talk all the time about how everybody was thin before and health means thinness and if we all ate like we did in some arbitrarily-selected point in time during which we were supposedly also well-nourished, we'd all be thin, too. what i find laughable is documentaries that push this particular view, the camera scrolling over faded sepia or black-and-white photos of this slenderer era... ignoring the people in those photos who were clearly obese, even then.

most people's idea of "obese" is totally screwed up, too. i'm supposedly not overweight... but by definition, if that were true i would be more than twenty pounds lighter. a woman from my old baladi class who was considered "chubby" or "overweight" was actually "morbidly obese" with a rack o' doom. when looking at the big scary numbers, people would do well to keep in mind that the terrifying epidemic of "overweight" is mostly made up of average-looking, perfectly healthy people, and the "obese" aren't that much bigger. the freak-show-level fat children from the maury povich show are aberrations, not the future of the world. and pretty much all of us, fat or thin, with the exception of people with interfering injuries or health problems that would be exacerbated by it, could benefit from some more activity and exercise. it wouldn't make many fat people into thin ones, but improved health makes just about anyone a little happier.

professional daydreamer said...

rachel: why should someone who is already healthy as they are have to "work at their weight?" what possible benefit could they derive from it? why can't we accept that people are meant to be in different sizes and give all of them the same basic human dignity we are all entitled to instead of making negative assumptions about their health, habits, and character based on love handles or a double chin?

even some of the researchers who believe that our current arbitrary definition of "normal" weight represents the human ideal will admit that although there might be certain health benefits associated with that number, naturally fatter people who diet themselves into fitting that smaller shape don't necessarily enjoy them.

Anonymous said...

I also find it bizarre, but not surprising, that there are people who are saying their anecdotal evidence and "beliefs" about genetics trumps the statements of a geneticist.

Ladies (and gentlemen), we need to always be skeptical, first and foremost, of those things which we have come to describe as "beliefs," *especially* when they have anything at all to do with science.

And the truth is, weight is as genetically determined as height, and that's *proven science* over at the very least 50 years, and not anecdotal evidence.

I know the idea of weight being as genetic as height is threatening to those who hold the belief that they can permanently change the shape of their body with the power of their will alone, but alas, one *cannot* permanently change the shape of their body, unless they're on the road to a suicidal eating or exercise disorder.

The idea that one can permanently change the shape of one's body is merely a message put forth by those groups that profit from your belief in it. If diets worked, why would the diet industry be consistently raking in 60 billion a year? They would be constantly losing customers who permanently lose the weight, right?

That's because dieting, and permanently changing the shape of your body, does *not* work. There are exceptions due to lack of information in the statistics (and I'm a mathematician, so I know what I'm talking about), but when it comes down to it, the vast majority of individuals cannot permanently change their weight, just as they cannot change their height.

The only difference is that weight can change temporarily, while height cannot. It's only a difference in the kind of tissue that comprises both systems --- adipose tissue is a bit more dynamic (though ultimately the cell count doesn't change), and bone is definitely not dynamic.