Why We Get Fat
The good news is recent research indicates fat might not be your fault. The bad news is you might not be able to do much about it
Genes, a virus, lethargy, or just too many fries: the possible causes of obesity are legion. |
A spokesman for the store later said that Rossi was fired for poor job performance. But the only reason Rossi could see for his dismissal was his weight. A high school football star, Rossi had struggled with obesity throughout his adult life. By the age of 21, when he started working at Kragen, he weighed 275 pounds. Over the next decade he tried everything from fasting to hypnosis and at one point had his jaws wired shut. On the day he was fired, Rossi weighed about 400 pounds.
Still, laudatory letters from customers and the company’s own evaluations were clear: weight had never affected Rossi’s job performance. So he decided to sue. Years later, in 1995, jurors awarded him $1,035,652 for lost compensation and emotional distress. They concluded that Rossi couldn’t legally be dismissed for a condition beyond his control. What convinced them, says Rossi’s lawyer, Barbara Lawless, was testimony from a medical witness that each person’s weight is controlled primarily by genetics—he attributed 80 percent to genes and only 20 percent to environment. [CK]
The jury’s decision reflects a profound shift in the way our culture views people who are excessively overweight. No longer can we equate significant weight with lack of willpower. With every passing month now, scientists announce the discovery of new genes and gene neighborhoods that can be associated with obesity. The count is up to 130 and climbing. In each of us, these genes combine to produce different results. Richard Atkinson, an obesity researcher at the University of Wisconsin in Madison, says, “If you think about all the combinations and permutations of those 130 genes, there are going to be dozens, hundreds, thousands of different kinds of obesity.” But knowledge is power, too. An understanding of the genetics of weight control is helping researchers develop a new generation of drugs for weight control.
Genes underlie the tendency toward toe tapping,
hair twirling, and other calorie-burning fidgeting.
What does it mean for a gene to be associated with obesity? Although all human beings share the same basic genetic blueprint, genes that make up that blueprint, or genome, vary from individual to individual. For example, imagine two people, each dressed in the same garments: underwear, pants, socks, shoes, shirt, and so on. If one wears a cashmere sweater and the other a cotton sweater, the one in cashmere will probably be warmer. But not necessarily. What if the cashmere-clad person is caught in an Arctic snowstorm while the cotton wearer visits a Florida beach? In that case, the one in cashmere will feel considerably chillier despite the warm sweater because of the different environment. Similarly, someone who inherits the version of a particular gene that’s associated with obesity will be more likely to wind up fat than someone who inherits a normal version, but that tendency can be affected by environmental factors such as how much fattening food is available. So once researchers have identified the genes of obesity, they must find out how the genes interact with a person’s environment.
By studying what makes mice obese, scientists hope to develop more effective ways for people to fight fat. |
The revolution in obesity research began less than five years ago with the landmark discovery of a gene for leptin, the weight-regulating hormone found in both mice and people. Fat mice and skinny mice flashed across TV screens around the world when scientists could finally say that the only difference between them was a single gene. Since then geneticists have uncovered many more weight genes. One, a gene mutation that is also associated with red hair, causes severe obesity. In its normal form, the gene produces a hormone that inhibits eating and also influences hair pigmentation. A mutation in the gene produces a damaged version of the hormone, or no hormone at all. In one case, researchers noticed that both a five-year-old boy and a three-year-old girl who had each inherited two copies of the faulty gene were obese by the age of five months.

News release from the University of Wisconsin
Richard Atkinson
Ways toWin at Weight Loss from the Food and Drug Administration
Obesity web links from the Mining Company




