Is Obesity Genetic?
Is obesity genetic? Well, yes. And no. Er….it’s complicated.
Many years ago, mainstream news outlets began reporting that scientists were trying to discover if there was an obesity gene. The question was on everyone’s mind: is obesity genetic? The later part of the twentieth century saw record breaking numbers in terms of obesity. This happened regardless of whatever advice the medical community offered up. Low fat diets, more activity, fasting- none of it has seemed to work. Who’s to say that obesity and genetics don’t go hand in hand?
The fact is, genetics do a play a role in your bodyweight. There are some lucky souls who can just touch a weight and look like a fitness model. These people make a great living standing in front of a camera or selling underwear. Then we have those who didn’t hit the genetic jackpot. Simply touch a carb and the waistline explodes. However, smart choices can help alter whatever genetic hand you were dealt. This is an explanation of how things are. It shouldn’t be used as an excuse to avoid change.
Consider this: everyone has different levels of nutrients in their bloodstream. As your body breaks down protein, fats, and carbohydrates, these by products can interact with neurotransmitters. Neurotransmitters kind of act like signals, and in this case, it’s possible that your body can get the thumbs up to eat more no matter how much you’ve already ate. We see this all the time with people who develop insulin resistance, which is a huge step in getting full blown diabetes. In this case your body is kind of immune to food intake, so it’s possible to devour an endless bowl of breadsticks because the body isn’t aware that it’s full yet.
Hormones also play a role. The chemical messenger leptin can control your appetite. Found in your fat cells, leptin is produced in high amounts when your bodyfat is high. In theory, people with more bodyfat should have less of an appetite (1). Your body is saying “I don’t need more food.” But signals can get crossed as leptin is supposed to inhibit another substance called NPY. It’s NPY’s job to actually slow your metabolism down and stir up your appetite. NPY is needed for those who are very active or have an extremely low bodyfat levels. It’s possible that leptin doesn’t stop NPY in some individuals so your appetite centers never get satisfied.
While some researchers believe that you have a set point for you weight, some scientists take things even further. The set point theory states that your body is reluctant to change and what’s to stay a current weight. But It’s possible that you have an “activity stat” located in your brain that has a predetermined level of physical activity (2). So an athlete’s brain simply stimulates the desire to be more active. The couch potato doesn’t get the same signals. You could argue then that people may not avoid exercise, but rather, they just don’t have any drive for it. Maybe there’s a deeper reason why your spouse keeps “forgetting” their gym bag at home before they leave for work.
So do your genetics play a role in your bodyweight? Of course. It’s estimated that there are over 340 genes that contribute to appetite, satisfaction, and where your body stores fat. However, it’s not fair to say that your DNA has sealed your fate. Awareness of your habits and mindful eating go a long way. As a personal trainer, I have to modify programs and movements to each individual, as everyone is different. But here are some examples of things that have helped UEFP client’s reach their ideal physique.
- Do some form of circuit training. Having to exert effort against a resistance will slowly increase your metabolism.
- Try to implement power training into your workouts. Think swinging kettlebells and throwing medicine balls. This type of training helps improve insulin sensitivity.
- Base each meal around a protein. This helps improve your satiety. It also helps keep your blood sugar levels relatively consistent through the day (it’s easier to store bodyfat when your blood sugar is all over the place).
- Your meal isn’t complete until you add a vegetable. Vegetables provide antioxidants, vitamins, minerals, and phytonutrients. These can all play a role in developing a healthy appetite.
1. Schwartz, M, Seeley, R. “The New Biology of Body Weight Regulation.” (1997) Journal of the American Dietetic Association. 97:54-58
2. Rowland, T.W. “The Biological Basis of Physical Activity.” (1998) Medicine and Science in Sports and Exercise 30:392-399 [/toggle]