The Internet can help you lose weight. But e-mail may be even more effective.

A study of overweight people found that weekly submission of calorie consumption and exercise diaries to a Web site and weekly dieting tip e-mails from a behavioral therapist helped them lose weight.
　　Those who participated in this six-month, interactive, Web-based dieting program lost, on average, 8.8 pounds after three months, and 9 pounds after six months. The study only followed the people for six months and was not as effective as in-person, noncommercial programs.

The results are in the current issue of the Journal of the American Medical Association.

The research, led by Deborah Tate, of Brown Medical School, in Providence, R.I., compared two types of Internet-based weight loss programs to see which was more effective. They split up two groups of people and monitored their dieting success.

In one group, 32 men and women attended an in-person weight loss group and were given access to the Internet with links to weight loss resources.

　　E-mail and Web Interactivity Worked

In the other, 33 participants attended the same in-person weight loss group, but also received 24 behavioral lessons via e-mail, and were asked to submit self-monitoring diaries (including exercise frequency and calorie counting) to which a behavioral therapist responded via e-mail. Additionally, members of this group could engage in an online bulletin board.

The study found that participants who received the more structured Internet behavior intervention cut their calorie consumption, lost significantly more weight and showed greater reductions in waist circumference at three and six months.

“The behavior therapy program was effective in almost doubling the percentage of participants who achieved a 5 percent weight loss goal,"the researchers say.

The Web-based interactive software is only a prototype, but some believe such types of programs could reach the millions of Americans struggling with obesity.

Michael Lowe, a member of the scientific advisory board of Weight Watchers International, called the interactive method a “good first step in the use of the Internet for weight loss."/p>

But more research needs to be done to tease out which of the interventions "i.e, the e-mails or the electronic monitoring "was most beneficial in achieving the results, says Lowe, who is also a professor of clinical psychology at MCP-Hahnemann University, in Philadelphia.

The study seemed to suggest that the behavioral support might have been more effective than the educational e-mails, Lowe says.

　　Which Intervention Helped?

Although the participants in the interactive Web-based program didn’t lose as much weight as those people who attend noncommercial in-person programs, Lowe feels the Internet can help people diet.

At university-based in-person programs, people can lose up to 20 pounds in 20 to 24 weeks, but most people drop out, like they often do in commercial programs, Lowe says.

People who try to lose weight on their own are more successful than those in programs because the severity of their obesity may not be as bad as those who seek out help, Lowe says.

“The vast majority of overweight people try to lose weight on their own, but they are usually unsuccessful," Lowe said. “The challenge for public health officials is to reach as many of them as possible with good methods. The Internet might be an effective way to get them."/p>

Frm ABCNews.com