It’s time for Halloween — a kid’s invitation to gorge on candy and a health-conscious parent’s nightmare. The swirling media frenzy around the nation’s obesity epidemic reminds everyone that we’re getting fatter. What’s worse — increasing evidence shows a link between excessive fructose and mental health, too. Short of nagging, how can you help your kids — and yourself — balance treats with the good stuff? Enter the mighty omega-3s.

A new study at the University of California Los Angeles looked at what happened to the brain when rats drank sweetened water versus when they paired the sugary stuff with a dose of omega-3 fatty acids.

Rats that consumed lots of high fructose corn syrup performed worse in a maze than rats that didn’t have the sweetener. But when rats had both sweets and omega-3s, the cognitive impact of the sugar was mitigated. The researchers say one explanation could be that rats who didn’t get omega-3s also seemed to develop insulin resistance, which plays a big role in learning.

Omega-3 fatty acids are found in common foods such as salmon, sardines and walnuts and in less-popular flax and chia seeds.

One study can’t give us all the answers and it’s certainly not meant to suggest eating too much sugar is OK. Eliminating added fructose from the diet is a tough, long-term prospect, so the researchers hope adding healthier options will help reduce the negative impacts to the brain. The researchers also advise people not to worry about the fructose in whole fruits, which doesn’t have the same effects. Fruit also provides much-needed antioxidants.

To keep trick-or-treating from tricking your child’s smarts, dole out a piece or two at a time or, better yet, have your kids trade in the sugary stuff for healthy snacks.