Wednesday, June 24, 2009

Genetics or Lifestyle?

What's more important? The genes your parents handed you or the foods they taught you to love?

I've been reading up on the debate about which factors are more influential - genetics or lifestyle - in maintaining a healthy weight. As you can imagine, it's pretty tough to prove either way. Maybe a person wasn't genetically predisposed to be obese, but their family's lifestyle factors influenced them in that direction. Or on the flipside - my father's family has been studied by the University of Utah because of the high incidence of obesity and yet not one of my siblings is overweight. I remember as a teenager my aunt telling me, "You're just a big-boned girl." (Loved that) Or the former Mr. Utah who taught me more about personal training than a university degree, "I love those thick Coats' legs." (As he grabbed my thigh during a lifting session.) Let's face it, because of genetics (and my ice cream addiction) I will never be a size two, but honestly, I'm okay with that. I just want to be fit and feel good.

I liked the four points that writer, William Saletan brings up in his article in The Dallas News, "Is genetics or lifestyle a bigger factor in obesity?"

"First, heritability by itself can't prove the limits of what environmental changes might produce. Environmental changes can significantly raise or lower average weight – as, in fact, they have – even if genes largely determine your weight relative to your peers.


Second, any environmental factor that affects the whole study population is too big to show up in the analysis. I'm not talking about things each family could do. I'm talking about things that affect nearly all families simultaneously: urbanization, pollution, the arrival of television and the proliferation of fast food.


Third, just because something is genetically caused doesn't mean it can't be behaviorally controlled.


Fourth, diet and lifestyle can themselves be genetic pathways. For example, fidgeting has been shown to burn lots of calories; it's highly plausible that fidgeting is genetically influenced and that it drives people to exercise. To the extent that genetics overlaps with fattening behavior, old dichotomies have to be chucked. You can't just blame fat people for eating too much. Nor can you assume that because fat is hereditary, there's nothing they or society can do about it." (i)

I think the bottom line is our propensity to be overweight or thin is definitely affected by our genetics but if we're one of those unlucky people who are more likely to be overweight we have to fight harder and employ all the tricks. It isn't fair, but hey, those skinny people have other challenges like, um, never being able to compete in sumo wrestling.

What do you think? Is lifestyle the determining factor or is it impossible to overcome your ancestry? 




  1. Thanks for stopping by...good question...I think genetics certainly can predispose you to being overweight, HOWEVER I feel strongly that behavior and lifestyle ultimately determine your waistline. Eating healthy...of course in're occasionaly icecream is a good thing...and having an ACTIVE lifestyle is the key to staying fit. Agree, that not everyone is a going to be a size 2...remember God likes VARITEY and we are not all meant to be a size 2...this would certainly not even be "healthy" for most of us. My motto is just eat right and're body will stay in check.
    Hope to hear from you again!

  2. Thanks, Roxy. Isn't it nice when you get to a point in life where you no longer want to be a size two?
    I appreciate your input and visit. I love your blog, of course I'll stop by again!

  3. I am definitely predisposed to obesity - at least on one side of the family. As you know from my blog, I run. I try to eat healthy. I'm going to fight the genentics!

  4. Good or you. It is so hard to fight, but so worth it.
    I will definitely always fight the good fight too.