Fat cells are the building blocks of flab, the wages of cheesecake, the bloated little sacks of grease that make more of us – more than we can fit into our pants. Scorned and despised, they are sucked out surgically by the billions from bulging backsides, bellies and thighs.
But they are not without admirers. “Fat cells are beautiful cells to look at”, said Dr. Philip E. Scherer, an associate professor of cell biology and medicine at Albert Einstein College of Medicine in New York. “I’ve been working with them for 10 years and I still enjoy looking at them”. On a recent afternoon at his laboratory, Dr. Scherer slipped a glass dish of fat cells under a microscope and showed a visitor how strikingly they caught the light and reflected it. Magnified, the cells became a field of glittering rings. A mature fat cell contains a huge, clear droplet of fat that takes up nearly the entire cell and shoves the nucleus aside, squashing it up against the membrane so that the cell appears empty.
Scientists used to think body fat and the cell it was made of were pretty much inert, just an oily storage compartment. But within the past decade research has shown that fat cells act like chemical factories and that body fat is potent stuff: a highly active tissue that secretes hormones and other substances with profound and sometimes harmful effects on metabolism, weight and overall health.
In recent years, biologists have begun to compare fat to glands, which also release hormones straight into the bloodstream. But there is an important difference. Glands cannot grow nearly as much as fat, which has a seemingly infinite capacity to make more of itself. Too much body fat can act like a poison, spewing out substances that contribute to diabetes, heart disease, high blood pressure, stroke and other illnesses, including some cancers.
Researchers trying to decipher the biology of fat cells hope to find new ways to help people get rid of excess fat or, at least, prevent fatness from destroying their health. In an increasingly overweight world, their efforts have taken on added importance.
by Denise Grady, The New York Times, 2004
ANSWERS
1. Excessive consumption of food with a high percentage of sugar
A. results in weight loss.
B. leads to the accumulation of fat cells.
C. ensures bodily comfort.
D. is a moral weakness.
2. A mature fat cell
A. contains a very small quantity of fat.
B. has no nucleus.
C. has no membrane.
D. is almost entirely made up of fat.
3. Scientists have recently demonstrated that fat cells
A. are static and inactive
B. are lively and energetic
C. hardly ever produce hormones.
D. prevent diabetes.
4. Glands
A. grow as much as fat tissue does.
B. grow less vigorously than fat tissue does.
C. secrete substances that cause heart disease.
D. destroy carcinogenic substances.
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