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Fat and Happy?

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Fighting the Thrifty Gene 3 pages: | 1 | 2 | 3 |

Nurture or Nature?

Photo of Pimas working outdoors
  Thanks to daily physical labor, Mexican Pimas are healthier than their sedentary American relatives

Ravussin, however, is quick to point out that our environment and culture are as much to blame for obesity as our genes are. The Pima of Mexico are closely related to those of Arizona; however, due to their labor-intensive lives and low-fat diets, the Mexican Pima do not suffer from obesity, diabetes or other associated illnesses. (For more on this topic, visit Feast or Famine) Though the Mexican Pima likely share the thrifty gene with their northern neighbors, their thinness is more evidence that an abundance of fatty foods and modern sedentary lifestyles are the real culprits.

"In humans there are some physiological mechanisms, but also a lot of cognitive mechanisms are important, too," says Ravussin. "For instance, you probably know you are going to eat at seven- regardless if you are hungry."

According to Ravussin, world governments are going to have to intervene. He speaks of "curing the environment, rather than curing the patients."

"There's no question these people suffer from a genetic disease," says Ravussin. "It's not sloth and gluttony."


"There will have to be public health policies to curb the obesity epidemic, such as playgrounds and safe places to play, taxing high fat foods," he says. "We tax cigarettes because they kill- well, obesity kills, too."

In an attempt to restore the health of the tribe, some Arizona Pima are turning back to a traditional diet, harvesting and preparing the desert foods their ancestors lived on. According to Ravussin, it's a good idea, but he doubts the desert foods can compete with cheap, ready-made processed foods.

"They want to have large quantities of food available all the time," Ravussin says of many modern Pima. "This is what progress is all about."

Photo of health check
  Ravussin measures the height and weight of the Mexican Pimas

Ravussin believes we all need to challenge that notion of progress to stem the wave that has crashed across the United States, most of the industrialized nations and now, much of the developing world. For example, people drive too much and walk to little, he says.

"Architects have to develop a better city," says Ravussin. "Instead of malls every ten miles, we need to return to main streets."
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