Stay away from high fructose corn syrup. Too much of the sweet stuff may make you stupid. That’s what a new study out of UCLA suggests. The scientists also found that the omega-3 fats in fish (including docosahexaenoic acid or DHA) can protect against the lapses in synapse function.

The researchers studied rats and found that a diet high in high fructose corn syrup hurts the brain, hampers memory and harms your ability to learn.

The scientists observed the rats’ ability to navigate a maze after being fed fructose.

“The DHA-deprived animals were slower, and their brains showed a decline in synaptic activity,” says Fernando Gomez-Pinilla, a professor of neurosurgery at the David Geffen School of Medicine at UCLA. “Their brain cells had trouble signaling each other, disrupting the rats’ ability to think clearly and recall the route they’d learned six weeks earlier.

“We’re not talking about naturally occurring fructose in fruits, which also contain important antioxidants. We’re concerned about high-fructose corn syrup that is added to manufactured food products as a sweetener and preservative.”