Wednesday, February 13, 2008

Are You Fated to be Fat?

A study was published last week to a great deal of media fanfare.

The study Evidence for a strong genetic influence on childhood adiposity despite the force of the obesogenic environment, published in the American Journal of Clinical Nutrition, details twin analyses whereby 5,092 twin pairs (some identical, some fraternal) were monitored for weight change. Comparing the weight change over time of identical twins versus those of fraternal twins was used to help determine the degree of nature vs. nurture on weight gain.

The researchers concluded that the vast majority of weight was heritable, or genetic in nature and in their discussion they make a point of noting,

"What is important is this finding means that “blaming” parents is wrong"
I'll come back to that in a moment.

First let's look at North America where roughly 70% of the population is now overweight or obese.

Clearly our genes haven't changed in the past hundred years or so, something the authors of the paper readily agree to.

So if our genes haven't changed yet the study is blaming obesity on our genes, why is it that obesity has become such a concern now?

George Bray perhaps said it best,
"Genes load the gun and the environment pulls the trigger"
So does that mean parents aren't to blame? Their kids have these fat genes and there's nothing we can do about it? They and worse yet their kids are fated to be fat?

No, though blame is a very strong word.

While certainly it's true that the interactions of genes with our obesogenic environment are what's responsible for the rapidly rising weight of the world, given the percentage of folks gaining weight, clearly those genes are pretty darn common. Therefore if you're a parent with however many kids and one or more of them are overweight or obese, at the end of the day does that mean there's nothing you can do about it?

Of course not.

While you can't change the outside environment, certainly your home's foodscape is within your explicit control. You're responsible for the foods in your cupboards, you're responsible for how much viewing time or internet time your children are allowed, and most importantly, you're responsible for both the example you set in terms of eating behaviours and also you're responsible for learning about nutrition, caloric intake and expenditure and healthy living as a whole and you alone are responsible for trying to pass that knowledge on to your kids.

Again, blame is a sharp word and if I'm going to wield it, I like to blame our government and public health systems for not providing parents with the necessary tools to properly understand the impact of the environment on weight nor the skills to maintain a healthy weight within our environment.

Long post short - 100 years ago obesity wasn't a problem; our lifestyles were different, which is why a time machine would serve as a fabulous weight loss aid. Certainly the environment is responsible for changing our lifestyles, however we can certainly still live responsibly within that environment, it just takes education, planning and organization.

The only thing your children are absolutely, for better or for worse predestined to be is related to you. Everything else is modifiable.

Bookmark and Share


  1. Anonymous6:05 am

    From my experience, the 'environment' has multiple components. One component is the 'foodscape,' the other is the tens of thousands of non-natural chemical compounds (which are not part of our human evolutionary history or environment) with which we have flooded our environment (including vast portions of our foodscape).

    In this context, our immune systems can get confused and interfere with the normal mechanisms for weight gain and weight loss. When a person is sensitive to these 'foreign' environmental factors, and is saturated by them, the immune system goes into a maximum defensive position and does everything possible to maintain the 'core' no matter how we manipulate the calories, food volume, and exercise.

    From my experience when 'environment' is referred to as one of the elements involved with weight issues, I look far beyond the foodscape.

    Radcliffe at Radcliffe's Weight Journal

  2. Anonymous7:58 pm

    Thinking about this for a minute.....

    I think this is one of those no-brainer/doh/no sh*t Sherlock things.

    Fat people have poor eating habits. They are consuming too many calories for their nutritional needs. And many are in total denial about it.

    If fat people have children then the children will be fed by people who have no idea about how to feed themselves properly let alone a small child.

    Children learn by example. If the example is fat with poor eating habits, then the children pick up poor eating habits and more than likely become overweight.

    I can't swear to it, but I remember reading somewhere that some research has been done which show similar findings with anorexia as well. Mothers who over diet, produce children more prone to eating disorders.

    I suspect what the "researchers" have found is people who are screwed up about food, produce children who are screwed up about food. Children share their parents' genes therefore it must be genetic.

    That poem was right "They f*ck you up, your Mum and Dad".


  3. I agree, parents need to take more time to control what foods they bring into the home. I am not a miser but when I stopped flavoured cordials, and the weekly out of takeout food, there was noticeable difference in the childrens behaviours. Our fridge is filled with fresh fruit, vegetables and juices. They don't miss out, yes they have the odd treat as we now call it and they do not expect to have it all the time. Getting them involved in outdoor activities and sports helps as well. The school they attend has healthy eating programmes and now the children accept that stuffing themselves on muesli bars, chips, cakes , cookies and soft drinks, icecream etc... is not good for their health. Many parents take the easy way out and fill kids lunch boxes with processed items and packaged goods. These foods are not alien to my children but they are also foods that they don't gorge themselves on either. I would much rather healthy children than ones who are obese and climbing the walls with all the extra sugar and preservative intake. McDonalds is the worst, even simple fries pushes them over the edge within half hour of consuming. Not all but a lot of it is plain parental laziness and ignorance.