After decades of inexorably rising rates of obesity among American youth, a new CDC analysis reveals a reversal of the trend. And best of all? The word ‘meat’ never appears in the report.

Ask any public health official about the most urgent challenge they face, and most of them would immediately identify the problem of obesity that has been a particularly intransigent problem among the youngest generation.

About the only thing that outnumbered the percentage of Americans of all ages considered overweight or obese has been the strident opinions about which magic bullet that government/schools/businesses/advertisers/food processors were supposed to fire to cure the problem.

We’re too sedentary of a nation, with too many drive-thrus and video games, so the solution is to get people to take up exercising, to stop watching and start playing more sports. But even as recreational and adventure sports have become billion-dollar businesses and gym membership grew to record levels, obesity continued to increase.

Others pointed to the fast-food purveyors and the decidedly unhealthy products that too many people consumers too many times a week — if only Americans would stop patronizing those restaurants, we’d see a big change in the statistics. But even as the entire industry reinvented its menuboard, offering salads and fruit cups and even vegetarian options, obesity continued to increase.

Veggie activists used the crisis to insist that there’s not an overweight vegan alive on Earth, and if only the entire world would abandon the foods that have sustained humanity for all of recorded history, the problem would be solved. Yet despite the somewhat modest growth in the numbers of people claiming to be vegetarians, obesity continued to increase.

Until now.

According to a comprehensive data collected by researchers at the Centers for Disease Control and Prevention in Atlanta, the national obesity rate among 2- to 5-year-olds dropped by almost half over the past decade, suggesting that a new generation of Americans may (finally) be able to avoid the risks of heart disease and diabetes linked to obesity.

Officially, obesity among young children fell from 14 percent in 2003 to 2004 to 8.1 percent in 2011 to 2012, according to a summary of the CDC data published last week in the Journal of the American Medical Association. The results expanded on data initially reported by CDC officials in October 2013.

In children and adolescents aged 2 to 19 years, obesity is defined as a body mass index (BMI) at or above the 95th percentile of CDC’s gender-specific, age-adjusted BMI growth charts. In adults, obesity was defined as a BMI greater than or equal to 30.

Why, you ask, has obesity declined so dramatically in the last several years, after decade upon decade of increasing incidence? Well, the CDC researchers were careful to state that “the reason for the decline in obesity among 2- to 5-year-olds was not clear.” But there are some helpful indicators.

A comprehensive plan

First of all, despite the rhetoric of single-issue activists, obesity is a multi-factorial, highly complex phenomenon with a constellation of causes that impact the incidence rate. That’s why the specific, seemingly positive changes noted above hadn’t made much of a dent in the problem.

Here’s a great example: Consider this list of undertaken in school districts across King County (Washington), where Seattle is located. The programs were part of a two-year federal obesity-prevention program called Communities Putting Prevention to Work.

Which one(s) on this list do you think had the most impact on obesity rates?

  • The Seattle School District replaced older equipment and supplies in its Physical Education programs.
  • Another school district began participating in the Commit 2B Fit campaign, in which 6,000 students and staff tracked and logged their monthly activities, with a point system awarding gold, silver and bronze “medals.”
  • In Auburn, Wash. (King County’s most obese community, by the way), a high school teacher and students belonging to DECA, a national student group that fosters entrepreneurship and leadership, put up signs in the cafeteria promoting the importance of breakfast and good eating habits, visited all the district schools to promote the initiative and brought in experts to talk about nutrition and fitness.
  • A Seattle elementary school promoted a “Stop Pop” movement.
  • The principal of a high school began riding his bicycle to work, swapped Coke for water in the school’s vending machines and began eating alongside students in the cafeteria.
  • About 100 students in one district got involved in CrossFit training in the middle and high schools, and many of them participated in a recent 5K run.
  • One school stopped giving doughnuts to students when someone did something good.

The answer: Nobody knows. In one sense, they’re all good. Are some programs better than others, or is it the collective impact of several overlapping initiatives that moves the needle? Are there combinations of program components that act synergistically? Do certain populations respond better to certain interventions?

No one has definitive answers.

The Healthy, Hunger-Free Kids Act of 2010 mandated that USDA set guidelines for local schools’ nutrition education and physical activity policies, and beginning in July of this year, more than 22,000 schools across the country serving low-income students will be eligible to provide free lunches and breakfasts to all students.

That’s all helpful and productive. But if there is one single measure that should rise to the top of obesity’s priority list — sorry, Coke and Pepsi —it’s a ban on soft drinks all day, every day in every school in the country.

If we’re going to get serious about rolling back the obesity crisis among children, it will take concerted action in a number of areas to affect their lifestyles. But for starters, how about a lot less bombast about “unhealthy” burgers and fries and more tough talk — and decisive action — to dry up the oceans of soda that kids and adolescents are swimming in?

Know how that works?

We’ve got to stop buying and drinking the stuff ourselves.

The opinions expressed in this commentary are solely those of Dan Murphy, a veteran food-industry journalist and commentator.