America needs to improve nutrition for its children.

Like charity, nutrition begins at home. This spring, the journal Pediatrics published a study that we found shocking: For 90 percent of young kids, potatoes, eaten as French fries, are their only constant vegetable, and most kids go days without eating any greens.

From 2005 to 2008 and then again from 2009 to 2012, researchers surveyed over 2,000 parents about their children’s eating habits and compared the data sets  — eating of green vegetables fell by half to only about 8 percent of preschoolers at the end.

The United States Department of Agriculture has guidelines that show preschoolers every day should eat fruits, vegetables, whole grains, protein, and low-fat dairy products. We urge families to follow these guidelines.

Brains and bodies develop best if kids eat healthy foods. And children form habits that last a lifetime.

But why should anyone outside of immediate family get involved? Because our society as a whole benefits if kids — and the adults they grow up to be — are healthy. At the same time, we all suffer when children fail academically — good nutrition has been show to equate with success in school — and when they develop health problems associated with either malnourishment or obesity.

When President Lyndon B. Johnson declared a war on poverty more than half a century ago, one battle in that war was to feed hungry children at school. The Child Nutrition Act that he signed into law in 1966 began the national school lunch program, which has since been expanded to include breakfast.

Just five years ago, our own state comptroller, Thomas DiNapoli, declared that childhood obesity had reached “epidemic proportions,” affecting a third of New York’s kids. Many of the children who live in poverty — and that is close to a quarter of all New York children — also struggle with being overweight because cheap foods are often not nutritious.

The comptroller’s 2012 report concluded childhood obesity cost the state $11.8 billion in health-care expenses the year before — and costs have only grown since then.

This is not someone else’s problem. Right here, in the school districts we cover, we have seen the number of kids who are eligible for free and reduced-price meals grow dramatically in the last decade. Rural Berne-Knox-Westerlo now has 40 percent of its students eligible. Suburban Guilderland has seen its eligibility numbers increase to nearly 15 percent, and Voorheesville last year had 10 percent of its students reach that threshold.

We were heartened then when, in 2010, President Barack Obama signed into law the Healthy, Hunger-Free Kids Act. The act, which went into effect in 2012, provided resources for schools and communities to use produce from local farms and gardens. It set minimum standards for wellness policies and used census data to determine need for means in high-poverty areas, authorizing meals in after-school programs in those high-risk areas. The act also provided for training those who make school lunches, and made nutritional facts about meals more accessible to students and their parents.

One part of the act caused consternation in some quarters — the act gave the United States Department of Agriculture the authority to set new standards for food sold in school lunches and vending machines. Some districts complained that kids didn’t like the healthier lunches and lunch sales fell off; also the healthier lunches could cost more to make.

Voorheesville, for example, recorded a 16.8-percent drop in the number of lunches sold to students in the first month of the program. “The bottom line is: The kids don’t like it,” said the Voorheesville business administrator at the time. Voorheesville students, the school board was told, were buying a meal for $2.75 and then throwing out the fruits and vegetables.

Voorheesville struck out on its own with a school lunch program before returning to the federal guidelines. Costs are reimbursed by the federal government for each lunch sold with the specified five elements — fruit, vegetable, protein, grain, and milk.

It can take time to acquire a taste for healthy foods; old habits die hard. In Guilderland, for example, which started introducing healthy foods two decades before the Obama program, there was no uproar over the federal guidelines.

We believe progress was being made, not just in the health of kids that get the bulk of their food through government-subsidized school meal programs, but with families at large who became educated through their kids — children get about a third of their daily calories at school — and through their schools about healthier eating habits.

In last week’s front-page story on school lunches at Berne-Knox-Westerlo, the district’s food service director, Deborah Rosko, told our Hilltown reporter, H. Rose Schneider, that sales had initially dropped as BKW, like other districts, it was required to serve 100-percent whole-grain carbohydrates and a wider variety of fruits and vegetables.

“It’s good for students, though,” said Rosko. “It’s just a matter for changing the way they perceive the food.” She called it a “learning curve.”

In New York, the State Education Department allowed districts to apply for waivers if they found the cost of whole grains too expensive so they could use the cheaper, less healthy processed grains. Those, numbers, too, show schools were adapting. Last year, 192 districts requested a waiver; that number was down to 137 this year.

In short, we were headed in the right direction.

So we are frustrated that the current administration is rolling back some of those healthy initiatives. The very same day that the Pediatrics study was released on preschoolers’ unhealthy eating habits, President Donald Trump announced plans to do away with sodium limits and with compulsory whole grains in school meal requirements.

Salt has no nutritional benefit and too much can be unhealthy. Some food producers for schools, because of the previous regulations, had already cut back on salt and had included whole grains in everything from burger buns to pizza dough.

The Trump initiative will reduce those influences on production. Kids who were learning to eat and like healthier foods may well backslide to their old habits and, if the rollbacks continue, schools may return to the cheaper, more popular but less healthy meals.

The move seems indicative of so much in the Trump administration — quick gratification at the expense of long-term progress.

We had a podcast conversation this week with Dawn Standing Woman, of Mohawk descent, and her husband, Eric Marzak who embraces Native American philosophies. He talked about the importance, before making a decision, of thinking of the seventh generation hence and the effect it will have on them.

This decision like so many others in the Trump administration doesn’t think even one generation hence. The $12 billion or more in annual health-care costs in New York State for childhood obesity alone far outstrip the costs of paying for whole grains in school meals.

And that, of course, does not even tally all the gains that cannot be counted in dollars and cents — the feeling of well being and the ability to focus and succeed, the sense of self-confidence and happiness that comes with good health.

— Melissa Hale-Spencer