When Theresa Finney of Northwest Washington quit smoking three years ago, she managed to kick her 30-year nicotine habit, but she gained 20 pounds in the process.

Without the solace of cigarettes, Finney said, she became "a dedicated between-meals eater." She stockpiled packages of Reese's Pieces and polished off an English muffin slathered with butter and peanut butter every night before she went to bed.

"I missed my friend the cigarette. Food became my friend . . ." recalled Finney, who gained all the weight within two months after she quit smoking. Since then, Finney has managed to lose all but five pounds.

Finney, 59, is a perfect example of a phenomemon shared by many ex-smokers, particularly women. The recently released Surgeon General's report on smoking cessation and health concluded that 80 percent of those who quit smoking gain weight -- the average is five pounds.

Not only is average post-cessation weight gain small, but the risk of a large weight gain is extremely low; fewer than 4 percent of ex-smokers gain more than 20 pounds after they quit, according to the report.

Nevertheless, the fear of gaining weight is one reason many smokers don't quit, the report says. And an aversion to getting heavier or the actual gain of several pounds may cause a relapse among many who do quit.

When she was "younger and more vain," weight gain was a major factor that prevented her from trying to quit, Finney said. Several people who attended a smoking cessation clinic with her three years ago dropped out of the program after they gained three or four pounds.

But the trade-off, to Finney and others, seems clear. As one Washington editor and ex-smoker put it bluntly: "I'd rather die a little fat than of lung cancer."

In fact, researchers generally believe that ex-smokers would have to gain 100 pounds to equal the health risk of continued smoking, said Jeff McKenna, chief of the health promotion section in the Office of Cancer Communications of the National Cancer Institute. The Surgeon General's report said that studies of former smokers who have gained small amounts of weight showed no significant changes in blood pressure, cholesterol and blood glucose; some studies have even demonstrated increases in the amount of high-density lipoproteins -- the so-called "good" cholesterol -- in the blood of ex-smokers.

Unfortunately, social pressure to be thin has made gaining even three pounds a real trauma for some women, said Harry Lando, professor of epidemiology at the School of Public Health at the University of Minnesota, who has done research on smoking cessation. There is some evidence that men may be more successful at quitting smoking because they are not as concerned about gaining weight, according to Tom Glynn, program director for smoking research at NCI.

Why both men and women gain weight when they stop smoking seems simple enough: They eat more. "They miss the mouth attention," said Catherine A. Lambert, regional director for Smoke Enders of Washington. "Your mouth has muscles. When it's not exercised, it feels funny. If you're a runner and you run two miles a day and then you don't run, you'll feel a difference."

Additional calories are often consumed in the form of sugar, according to Glynn, who said that intake of simple carbohydrates seems to rise after smoking cessation, although it's not clear why.

Hoarding candy bars may not be the only reason ex-smokers gain weight. Some do so even though they don't eat more. Several studies have found that smokers have faster metabolisms, according to Lando. When they quit smoking, their metabolisms -- the rate at which their bodies burn calories -- may slow down, so they gain weight, although this response is often temporary.

Good health habits, such as drinking plenty of water, snacking on raw vegetables or rice cakes and getting moderate exercise can help. Relaxing in a hot bath can relieve stress better than smoking or eating.

Health authorities say quitting should be the first priority for smokers. NCI officials advise that smokers not attempt to diet while giving up cigarettes. Those who do gain a few pounds should focus on taking them off after they've quit smoking.Eating Right appears on alternate Tuesdays.