With Americans' obesity driving the focus on weight loss, scant attention is paid to the other side of the scale _ underweight people who are trying to put on pounds.
Being underweight is not a common problem in the United States, affecting only about 2 percent of adults, compared to two-thirds who are overweight or obese. But people who are too thin can be vulnerable to disease because they may have weakened immune systems; they are also at higher risk of osteoporosis.
There are varying reasons why a person may be underweight. Some may have fast metabolism and burn calories off quickly. Others may be recovering from an eating disorder like anorexia or bulimia or from the side effects of disease such as cancer or AIDS.
People looking to shrink their waistlines often have a wealth of information to reach their goals from diet books to weight-loss programs to support groups. But for those wanting to fatten up, it is often a lonely struggle.
``We are so preoccupied with the idea that people might gain too much weight that we almost don't want to admit that any weight gain is normal,'' said Joanne Ikeda, the co-director of the Center for Weight and Health at the University of California, Berkeley.
Erika Wallace, a 27-year-old media transcriber from Atlanta, found this out firsthand. Whenever she confides to her friends about the hardship of gaining a mere pound, they shrug her off, telling her she does not have a ``real problem.''
Wallace has been naturally thin all her life. At 5-foot-4, she weighs only 100 pounds. That gives her a body-mass index of 17.2. Anything under 18.5 is considered underweight.
Wallace scarfs down three meals a day _ grits, eggs and bacon for breakfast, sandwich, chips and fruit for lunch and chicken and vegetables for dinner _ and snacks between courses.
``I eat all day when I'm in front of the computer. I'm constantly stuffing my face to gain weight,'' she said. ``You get tired of eating sometimes.''
Despite her efforts, Wallace struggles to maintain the extra pounds. She would gain a fleeting three pounds only to revert to her regular weight if she missed a meal. Wallace recently joined an online chat room for underweight people on WebMD, a commercial health Web site, where she posts her food diary and gets feedback from like-minded peers.
``Everyone is so obsessed with trying to lose weight that there really isn't much out there for people trying to gain weight,'' said Martha McKittrick, a staff dietitian at the New York Presbyterian Hospital and a health expert at WebMD.
While there isn't a one-size-fits-all plan to weight gain, the key is to take in more calories than you burn. Consuming an extra 500 calories a day usually leads to a gain of a pound a week.
People suffering from eating disorders or the side effects of disease must first break through mental and physical barriers before they can start counting pounds. For the naturally underweight looking to beef up, health experts advise eating five or six times a day, spacing the meals throughout the day to avoid feeling stuffed and keeping in mind that not all foods are created equal.
Choose nutrient-rich foods like bread, cereal and pasta and dairy-based products like milk, cheese and yogurt. Snacking on high-calorie avocados, nuts and dried fruits is also a good option. Lay off the sugary soda and junk food, which only add empty calories.
``You still can't eat cookies in front of your television willy-nilly,'' said Cathy Nonas, a spokeswoman for the American Dietetic Association and director of the obesity and diabetes programs at North General Hospital in New York City.
Exercise is important too. Not only does staying active help stimulate appetite, it helps build muscle and avoid flab.