ATLANTA (AP) -- It's just passing up a soft drink a day, taking a few extra steps to deliver a phone message by hand instead of by e-mail, or not vying for the closest mall parking space.

Over time, the little things you do -- or don't do -- will add up in a big way, by turning lost calories into lost pounds.

That's part of the government's new "small step" campaign to trim the waistlines of Americans. Under the new push, announced Tuesday, the government says people don't need extreme measures to lose weight -- such as following a strict diet or joining a gym.

Obesity experts say small steps not only are what's needed, they also represent a major change in how health officials are tackling the country's belt-bursting weight problem.

"To have that kind of message is an enormous step and will be very important to the health of our nation," said Madelyn Fernstrom, director of the Weight Management Center at the University of Pittsburgh Medical Center.

Cutting 100 calories a day -- about a can of Coke -- can lead to a 10-pound loss over a year, Fernstrom said. Using the stairs rather than an elevator can also help with weight loss.

"We like to eat like farmers, but we don't work like farmers," she said. "We have to do something -- we are failing because everybody's getting fatter."

Obesity is a life-or-death struggle in America: It was the underlying cause behind 400,000 deaths in 2000. If current trends persist, it will be the nation's No. 1 cause of preventable death, according to the federal Centers for Disease Control and Prevention.

In the past, health experts recommended more stringent ways to cut the fat, from sticking to a diet of 1,200 calories a day to exercising at least 30 minutes most days.

Some experts say those fat-cutting plans likely contributed to the nation's epidemic by turning countless people away from exercise and healthy eating habits.

"It doesn't have to be hard labor to make changes in lifestyle to have a long-term payoff," Fernstrom said, adding that the government's new push is "less punitive. You're not locked into a program, you can proceed at your own pace."

Yet the idea has critics. The government push is "more talk and no real help" for millions of Americans, the Center for Science in the Public Interest said in a statement.

The people most likely to benefit from the campaign will be the majority of Americans who are mildly overweight or who are maintaining their weight. While obese people may be motivated by the government's effort, they likely will still have to use drug or surgical options to overcome obesity, experts said.

But other experts applauded the slower approach.

"What we really want to do are slow and steady changes," said Dr. Henry Anhalt, director of the division of pediatric endocrinology at Children's Hospital of Brooklyn at Maimonides. "If we swore off elevators and decided to take public transportation and get off one stop earlier, we would make tremendous headway."

Urban planners could help by designing sidewalks and parking lots that encourage walking, Anhalt said.

The government also should focus on schools, many of which have eliminated physical education classes while obesity has tripled in the past two decades among adolescents, said Dr. David Satcher, who was surgeon general when the government released its first obesity report in 2001.

Some Georgia schools don't even have recess any more, he said.

"I have no objection to small steps -- I really think there also need to be big steps," said Satcher, a former CDC director and current director of the National Primary Care Center at Morehouse School of Medicine.

"This epidemic requires a very aggressive response," he said. "We're going to have to spend some money to prevent it, we're going to have to afford physical education in schools."

Copyright 2004 The Associated Press. All rights reserved.