By Maggie Shiels In California

Obesity is about to get cut down to size as America declares it public enemy number one.

Everyone from Congress to the surgeon general is weighing in with legislation and programmes to improve the nation's eating habits.

The Internal Revenue Service is even allowing all Americans deemed as obese to be able to write off costs for weight-loss plans as a genuine medical expense.

A number of stalls offer students a healthier option

But the most radical move is that taken by one of the States' biggest school districts. Oakland, which lies to the east of San Francisco, is said to be the first school district in the nation to enact a system-wide ban of all junk food from its buildings.

Brian McKibben is the principal at Oakland's biggest school, Fremont High where soda, candy, caffeinated drinks and other similar products are no longer sold on campus.

Overweight, out of shape

"Since I am recovering from heart disease myself, I am very sensitive to both diet and exercise, and anything we can do to make it better for the kids, I want to do," says Mr McKibben.

The motivation for the move is simple. A recent survey shows that California, with its image of bronzed, buffed bodies, has a hefty student population.

What we are doing is good - just look around, there are a lot of fat people everywhere

Carlo Perez, student

Some 30% of youngsters are overweight, 77% are out of shape and 98% have diets that fall short of national nutritional standards.

Nationwide, the land of the free boasts 54 million obese adults, that's people who are 30 or more pounds over the healthy norm based on height.

Health groups say one of the biggest culprits for this growing epidemic is junk food, and that the best time to break the cycle between obesity and bad eating habits is when people are young.

Mikel Calderon, a 16-year-old Fremont High student, backs his school's ban.

Sugar free

"Even though most people go for junk food, I think it's better to get them out of eating potato chips and sodas and turning their bodies into a mess," he says.

"I think everyone should be concerned."

Students count their takings from the stalls

At Fremont there are healthy alternatives to the fat and grease peddled at the local burger bar or taco lounge. The school's business academy operates a thriving operation selling sugar free fruit juices and nutritious food made by local merchants.

"What we are doing is good," says 16-year-old Carlo Perez, who helps run the business through the school's Students In Free Enterprise programme.

"Just look around here. There are a lot of fat people everywhere."

Fellow student David Ingrams disagrees. "Junk food is good for the body. You can't live without junk food in your life. Who lives on vegetables every day?"

Limited success

With such attitudes common among teenagers raised in a fast food culture, Business Academy assistant director Amy Carpenter says education is the way forward.

"Just saying 'eat this' and 'don't eat that' kind of creates a whole air of prohibition about it so that maybe that candy and that soda pop becomes even more desirable," she says.

They can eliminate everything they want and it will not do one thing to curb obesity - Yyou cannot mandate fat away

John Doyle, Centre for Consumer Freedom

"So I think the key here is that it comes from within students so they change their minds about how they look at nutrition."

Fremont High's attempts to trim its student body is only having limited success.

Around 200 teenagers tuck into the healthy low-fat fare, which generally sells out every day. And the cafeteria can only cater for another 100 pupils. That means there's 1400 students with nowhere else to go but the nearest corner market for cookies and soda or the local Burger King for fries.

Costing dearly

Ms Carpenter admits this does slightly defeat the purpose of their junk food ban.

"That's one of the reasons we are looking are partnering with peer health educators to change the minds of our consumers and create a bigger market so that we can sell healthy food to more kids as an alternative."

Student Amy Carpenter says education is the way forward

The food industry is fighting back running adverts that criticise "food nags" for taking away choice.

The Centre for Consumer Freedom lambasts Oakland's ban as the most extreme in the nation. And spokesman John Doyle claims: "They can eliminate everything they want and it will not do one thing to curb obesity. You cannot mandate fat away."

Efforts to slim down Oakland's students could cost the district dearly. Nationwide, fast food contracts bring in around $750m a year. Oakland's ban will cost roughly $650,000, with individual schools losing around $200,000 of much needed money that is often spent on field trips and sports.

But Fremont's Principal Brian McKibben says this fight is about more than dollars and cents.

"There are some real issues here that involve corporate greed. What is more important? The bottom line for the corporation in terms of its profit or the health of human beings?

"That's a real concern for me."