The question of whether obesity is nature or nurture has been answered a long time ago. It is a combination of both. It is not a coincidence that children of obese parents are obese, while children of athletic families tend to be, well, more athletic. It is also no secret that food habits of the obese trickle down to their families and children, and perhaps even as important, healthy lifestyles are contagious and fulfilling.
The proof of genetic predisposition can be found everywhere you look. You probably need to look no further than your own circle of friends or acquaintances. We all know someone who eats more than we do, does not exercise, and stays as thin as
can be. We are all jealous of the friend who will live off junk food and sodas, have absolutely zero gym memberships, is practically allergic to exercise, yet stays fit and trim. Why is that? You can thank his or her genetics for that. The flip side to that conversation is people who barely eat yet put on weight. No matter how you think of it, the simplest equation that determines obesity is the amount of energy coming into our bodies exceeds the amount of energy spent by us. The end result is storage of excess energy as fat.
So, what do genes control? Scientists have figured out by studying families, twins and other groups that genes and our DNA seem to determine how we cope with changes in the environment. That is a very powerful adaptive tool. Those of us who cope well with change, who adapt to their environment and the new demands or stressors or foods tend to remain thin. Further, DNA determines our metabolic rates (which can be somewhat regulated by the foods we eat and exercise). Some of us will have a high metabolic rate and that helps in energy expenditure. Some genes control our drive to eat, or in the obesity case, overeat. The reality about genes is that there is usually a complex interaction between several of them. Rarely is obesity related to a single gene or DNA sequence.
As far as the environment is concerned, well, how about you help me count the many ways our environment has become conducive to obesity? Ready: lack of physical activities, increase sedentary activities, restaurants and specifically, fast food ones, increased animal proteins in our diets which have more fat in them, more television, more technology, and so on and so forth. There is no doubt that we are getting more obese.
The fight against obesity needs to target our genes and our environment. It is a combined attack that targets our life styles, our predispositions, our preferences, our convictions and beliefs, our histories and core make up. The fight is one that encompasses many factors. Each one has his or her own unique battle. The war is the same. The strategies are different yet comparable. As it stands, we are losing the war. But winning starts with fighting daily battles and winning them. For us to stand a chance of conquering, we need to understand who we are, what we are, how we are where we are. For that, look no further than genetics, and our environment.