Currently viewing the category: "genetic theory of obesity"

I’ve gotten to experience something very interesting over the last couple of weeks.  Resulting from my posts on childhood statin recommendations and parental responsibility for childhood obesity, I’ve gotten numerous replies, comments and tweets that have both commended and criticized my views.  Being all for intelligent discussion, I’ve welcomed the responses; but something has become very clear to me: People who are attached to a particular point-of-view will fill any holes with their own interpretations and opinions,quite apart from anything that has ever been said or implied.  It’s an interesting phenomenon.  So as promised, I will continue presenting my viewpoint on obesity in general, and specifically, childhood obesity, so I can fill those holes myself, and keep my thoughts from being assumed by others.

Let me begin with the obvious: What is obesity?  From Wikipedia:

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems.  Body mass index (BMI), a measurement which compares weight and height, defines people as overweight (pre-obese) if their BMI is between 25 and 30 kg/m, and obese when it is greater than 30 kg/m

Wikipedia is not necessarily the end all be all as a reference source…but, in this case…well, it’s right.  Weight gain, which can lead to obesity, is caused by taking in more calories than you burn, period.  It doesn’t happen from eating one tootsie roll, despite a tootsie roll being an unhealthy food-like item, or from eating one French fry, or even thirty on a Saturday night for that matter; nor does it come from eating a Twinkie, or a bag of chips, or drinking a soda.  No, gaining excessive weight, and developing obesity, comes from eating lots of crap over and over again.

It is what one does repeatedly that matters, so, in that regard, obesity is a calorie issue.  But yes, there is more to it, although I would argue very strongly that the most important factor is overeating.  As a rule, Americans eat too much.  Listen, I am an American.  I eat at restaurants.  My observation is that the portions served in most restaurants are more than most people need under most circumstances.  I also observe how others eat, and can say quite confidently that most people aren’t leaving their plates half-full.  No, most people put it away–all of it–plain and simple.  And this (as a habit) leads to excessive weight gain.

Here’s some basic nutritional physiology: Take in more calories than you expend, you gain weight.  Expend more calories than you take in, you lose weight.  When intake and output (over time) are relatively equal…you maintain weight, no gain, no loss.  Duh.  It blows me away that some people actually try to argue against this simple fact.  Why not, then, argue against the Pythagorean Theorem while you’re at it?

Listen, it doesn’t make sense to try to disprove what we already know about any science.  If it’s an established principle, why try to reinvent the wheel?  Oh no, the Law of Gravity is wrong, and that’s why we can’t unify all theories on physical forces.  No serious thinker would go that route.  Instead they would take what is already known and try to formulate a theory around that.  Freakin’ duh!   So why do some self-proclaimed experts attempt it with nutritional physiology?

There is no doubt that food types matter when it comes to weight gain and obesity.  It doesn’t take a brain surgeon to understand that French fries are a worse food choice than broccoli.  And it doesn’t take a theoretical physicist to understand that eating wholesome foods, as a habit, is better than simply cutting your French fry intake in half.  Freakin’ duh!


What amazes me is that some people think that somehow my previous posts suggested that I advocate a low calorie diet.  When have I ever said that?  Let me be perfectly clear: I’ve never said anything about a diet of any sort.  When I speak of “diet,” I speak in terms of how one eats, the types of foods one eats, and NOT a freakin’ fad diet (and that includes Atkins, or rehashed Atkin’s-like theories).  I simply cannot be any clearer.  The types of foods you eat matters, and how much of them you eat matters too, and how much you burn with physical activity also matters a whole hell of a lot more than your mutated skinny genes (and you thought those were just clothing trends).

Interestingly, the notion that calories in vs. calories out and food type both contribute to obesity presents somewhat of a conundrum to people battling weight.  Some will say, “I don’t eat junk food, and I just cannot seem to lose weight.”  Then you eat too much, is my answer.  No, I don’t eat too much.  Then the types of foods you are eating are poor choices.  No, that’s not it either.  Okay, then what is it?  It’s genetics.  Oh, you mean fatness runs in your family.  Well, no…I have a gene.  But nobody else in your family is fat?  Well yes…both my parents.  Listen that’s called nurture–what you were exposed growing up, your learned behaviors–not necessarily genetics, or nature.  All you are doing when you blame it on your genetics is pulling yourself out of the equation, and I’m sorry, but that just doesn’t cut it.  Genetics, hormones, lack of sleep, blah, blah, blah…yes, okay, they contribute…but not more than your food choices do, both in quantity and quality.

I’m going to discuss hormonal factors in weight gain in the next post on the subject, as well as list some factors that are primary in the development and maintenance of obesity.  Just remember that food choices matter–the types of foods you eat (whole, natural foods that you prepare yourself are best), as well as how much you eat.  Denying basic physiological principles isn’t going to make one dent in the obesity epidemic, so the fools doing just that are merely perpetuating the problem.

Just read a great article on human evolution and how advantageous traits are likely selected for over time.  It got me thinking again about the genetic theory of obesity.  Now you all know how I feel about this subject–I pretty much find it a convenient excuse to absolve obese people from their personal responsibility.  Put another way: Gene or no gene, you’ve still got to eat well, exercise, and practice discipline.  Hey, we all have to that.

But reading this article in the September issue of Scientific American (I know I’m behind…cut me a break…I’ve got kids) titled, How We Are Evolving, got me thinking that obesity very well may have a genetic link.  According to recent research, most traits that provide genetic advantage or disadvantage likely take tens of thousands of years to disseminate throughout a population, not the thousands of years a high frequency mutation was once thought to dominate natural selection.  I won’t get into the science here; read the article to get the details–it is excellent.  Suffice it to say that the data shows evolution to be a long, drawn-out process, as natural selection takes time.

Okay, so what about obesity?  Well, let’s just say there is a gene, or genes, that increase one’s susceptibility to becoming obese; we might just find that that genetic makeup actually does lead to enough of a disadvantage that it eventually gets selected out of the human genome.

Think about it like this: obesity offers a disadvantage by making a person more susceptible to illness and disease–like many cancers, heart disease, stroke, and the list goes on and on.  Up until now it hasn’t conferred enough disadvantage to be selected out of the population–that is, obese people can still pass on their genes.

However, as more of the population gets obese–34% of all adults in the U.S. and 300 million worldwide–less and less may find the opportunity to reproduce.  What do you mean, Campos?  Just a thought, but when approximately 20% of our children here in the U.S. are obese…that’s a BMI over 30!…there may come a time when these people are just not considered reproduction material.

Biologically speaking, organisms seek out the most fit individuals with which to mate so that the possibility of passing on one’s genes increases.  That’s the idea anyway.  As the numbers of obese individuals increases, as well as society’s disdain (just read the news!) for obesity, you might just see more of these people ostracized sexually.  Not large numbers right away, mind you–this is where the article got me thinking–but over time.  Could be tens of thousands of years.  Remember, natural selection works slowly.  I mean, things would really have to change societally for this to be considered no big deal.

And yes, obese mating with obese is always a possibility, but that will simply raise the risk, in my opinion, for the genes to become selected out.  This, of course, all predicates on whether a genetic cause (susceptibility?) of obesity actually exists.

My advice to everyone is, once again, gene or no gene, you can prevent obesity by doing the right things.  If my thoughts are correct–and sorry, you and I will never get to know–then you’ll be assuring your genes get passed on to future generations by removing and preventing obesity in your life.  Just a thought, anyway.

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