My Mom Made Me Fat: How Genes Affect Obesity

If you want to be lean and healthy, eat right and exercise regularly. If you want to be very lean, get different parents. That's the bottom line when it comes to genetics and obesity. Research over the past decade has demonstrated repeatedly that while diet, activity level, and other lifestyle factors affect body weight, genetics has a huge impact on a person's response to those lifestyle factors. But that doesn't mean that less-than-stellar genes irrevocably doom a person to a life of obesity, diabetes, and cardiovascular problems. Understanding how lifestyle choices turn these "fat genes" on and off can help you lead a healthier life.

Exercise

Everyone has that friend who can eat anything she wants, never set foot in the gym, and still be thin. Conversely, we all know someone who works out religiously and has a wonderfully healthy diet, yet struggles with body weight. These factors can be attributed to genetics. But even if you didn't have the good fortune to be blessed with "thin genes," you can reap the benefits of exercise. Exercising for as little as thirty minutes each day has a suppressive effect on the genes that promote obesity. Even avoiding the elevator and taking the stairs or parking in the back of the lot to increase the number of steps you take each day can help turn off your "fat genes."

Diet and Lifestyle

The field of epigenetics examines the relationship between external factors, like diet, sleep, and exposure to pollution, and how genes are expressed, or turned on and off. Recent and ever-expanding research in epigenetics reveals that there is more to a healthy diet than fats and calories in and out. Studies using mice that were developed to become obese easily show that substances in food such as B vitamins tend to function to turn off obesity-promoting genes. In contrast, high-fat diets and alcohol work to turn on these "fat genes." The end result is that fat- and alcohol-laden diets pack a double punch: they are rich in calories, and they also encourage the body to store increased amounts of fat.

Beyond diet and exercise, environmental toxins, air quality, and amount and quality of sleep all influence whether obesity-promoting genes are turned on or off. Lack of sleep and stress promote the body's production of the stress hormone cortisol, which turns on "fat genes." Pollutants can act directly on DNA, altering how it is expressed and resulting in an increase in the number of "fat genes" that are turned on at any given time.

Future Generations

Recent research even suggests that your personal lifestyle choices have impacts that reach beyond your own lifetime. The "on" or "off" state of obesity-promoting genes in your body can be passed down to your children, making it easier to turn their "fat genes" on or off. Sleep deprivation, stress, high fat diets, and lack of exercise can make the next generation more likely to have easy to turn on "fat genes." Conversely, exercising regularly, eating a balanced diet, and avoiding exposure to toxic chemicals can result in your children's obesity-promoting genes being stuck more firmly in the "off" position.

You may not be able to do anything about the genes you have, but your lifestyle can influence how they behave. By leading a healthy lifestyle, you can encourage your "fat genes" to turn off, allowing you to experience better results of your diet and exercise efforts. In the future, treating obesity may involve medications designed to turn of obesity-promoting genes, but for now, the best tool available is lifestyle.