Over the holidays, most families will indulge in sugary treats. But before you offer your child a candy cane or chocolate coin, consider what research tells us about how kids perform in math is affected by what they eat for lunch – and consider making some new holiday traditions.

It may seem like a few candy canes and cookies won’t really pose much of a threat. But two potentially harmful things can happen when kids fill up on sweets. First, as your mother may have told you, a child who is full on sweet treats has less room for more nutritious food. Secondly, since sugar apparently has addictive qualities, those who eat a sugary treat could potentially crave more. So rather than let your child fill up on holiday-themed junk food, it would be better to cut back on the sweets and help build on healthy eating habits more kids are learning at school.

The position I take is based on extensive research that my colleagues and I at American University have conducted into the connection between nutrition standards in schools and academic performance. We conducted this research following the implementation of Washington, D.C.’s Healthy Schools Act of 2010.

While more research is needed to better understand the specifics of the relationship between nutrition and learning, it is clear there is a link between classroom success and diet habits.

Our own research found that children in D.C. who attend schools with healthy school lunch options, more time for physical activity and more messages about health were more likely to perform 10 percent better in mathematics as measured by the district-wide achievement test.

But, of course, it’s not just the food consumed in school that matters. More than 30 percent of children in the United States are overweight or obese. It is well-established that these children are at increased risk now and in the future as adults for Type II diabetes, hypertension, and bone and joint problems that were once largely confined to adults. However, these types of physical diseases are not the only serious threats to children’s health and well-being. Researchers are finding that obesity is linked to the emergence of cognitive deficits that begin in childhood and continue throughout life. In fact, brain disorders associated with Alzheimer’s disease and other late-life dementias may begin at least 50 years before those disorders are clinically diagnosed. Poor eating habits at home and school can keep students from being successful in the short term, and have detrimental effects long term.

We found the positive relationship between the combination of physical activity and nutrition and mathematics performance was biggest at schools with a higher percentage of students receiving free and reduced-price meals. This suggests school meals tend to be more healthful than those brought from home. It could also mean that kids at these more disadvantaged schools had the most to gain from putting in a free lunch program.

The Healthy Hunger-Free Kids Act set new nutrition standards such as access to local foods, more fresh vegetables and fruits, and low-fat dairy products that schools must follow to be a part of the Agriculture Department’s school lunch program. School districts and their food service offices responded quickly to develop meals that would meet the new nutrition standards and that kids would still want to eat. But in many instances these healthier meals have been met with resistance from both parents and students.

Despite that pushback, there has been increased attention toward boosting the consumption of healthful foods in school cafeterias. This is good news for our students, because research) shows that consistent exposure to healthful foods at school and home can increase long term healthy eating, especially in younger children.

For instance, one study found that, in large part, food “preferences were stable from 2- to 3-year-olds until young adulthood.” Another study found that one of the “strongest predictors of the number of foods liked at age 8 years…[is] the number liked at 4 years.”

In Washington, D.C. and Arlington, Virginia schools, research has shown that by letting students help select how vegetables are prepared or pairing a fruit and vegetable, we can get them to eat more healthful foods.

Such efforts are crucial because – as we have established – helping kids develop a taste for healthful foods early in life sets them on a path to better school performance and becoming a healthier adult.

Will a few extra treats during the holidays mean the difference in your child’s academic career? Probably not. But by emphasizing healthy eating during the holidays, parents can help their children hold onto healthy habits that will last them a lifetime.

Sarah Irvine Belson receives funding from the National Science Foundation, the Toyota USA Foundation, and the US Department of Agriculture.

Anastasia Snelling receives funding from the National Institute of Food and Agriculture.