"You are what you eat" has truth to it, especially when you consider how certain foods can impact your brain health. Previous studies have touted leafy greens for their cognitive benefits, while kefir has been linked to improved memory and decreased levels of inflammatory cytokines. Now, new research has found that swapping unhealthy snacks for one specific option—pecans—can also keep your brain sharp.

Here's exactly what the new study found and how many pecans you need to snack on to experience their instant brain benefits.

RELATED: Doctors Say Avoid These Snacks Like the Plague

Pecans are packed with naturally occurring compounds that aid brain health

The rich, buttery nut is packed with more than 19 vitamins and minerals, including vitamin A, magnesium, potassium, B vitamins, and zinc, per the National Pecan Shellers Association (NPSA).

Pecans are naturally sodium-free, good for your heart, and an excellent source of protein and fiber.

And now, a new study published in the journal Nutritional Neuroscience is raising awareness about pecans’ benefits for your memory and cognitive function. This is due, in part, to the fact that pecans "have the most polyphenols of any tree nut," according to the authors.

Polyphenols derive from "natural foods with vibrant colors," per Cleveland Clinic Health Essentials. Examples include blueberries, strawberries, turmeric, and leafy greens. They contain antioxidant and anti-inflammatory properties that help fight oxidative stress, heart disease, aging skin, and some cancers. Researchers also believe polyphenols are beneficial for brain health.

Pecans can improve attention, processing speed, memory, and learning

Shutterstock

For the study, 31 healthy adults (ages 18 to 30) were randomly divided into two groups. In one session, one group drank a pecan-enriched shake while their peers consumed a chocolate shake (the control meal). The groups switched meals in a second session. Both shakes contained the same amount of calories, sugar, fiber, and fat content—although the chocolate shake was significantly higher in saturated fat.

A third party was responsible for giving out the shakes, so neither the researchers nor the participants knew who was drinking what. Additionally, participants had to adhere to a specific diet (50–55% carbohydrates, 15–20% protein, 25–30% fat, and no polyphenol-enriched foods) prior to each session.

At the beginning of each session, participants were assessed for sleepiness and motivation, then completed 23 different cognitive tests. Afterward, they drank one of the two shakes, then took the cognitive tests again after one hour, two hours, three hours, and four hours. The researchers also gathered and evaluated their blood samples.

The results of the experiment showed that after drinking the pecan shake, participants scored higher on eight of the tests: four related to attention and processing speed, and four related to memory and learning.

“This work indicates that incorporating pecans into the diet of healthy young adults can elicit acute benefits to cognitive performance and may lead to pecans being considered a cognitively protective dietary source,” said the study authors concluded.

However, the study had its limitations, especially when it came to sample size. Further research, with a more diverse patient pool, is needed to better understand the long-term brain health benefits of pecans.

RELATED: Scientists Say Adding This "Brain Food" to Your Diet Can Keep Your Mind Sharp All Day

How to incorporate pecans into your diet

Still, this new research suggests that pecans can be a healthy snack that may offer brain benefits in a matter of hours.

Plus, it's widely known that the nuts can also help you lower your cholesterol. As we've previously reported, a study in the American Journal of Clinical Nutritionfound that replacing daily snack foods with pecans "improved cholesterol levels and enhanced overall diet quality."

Participants reported a reduction in total cholesterol, LDL ("bad") cholesterol, and the ratio of "total cholesterol to HDL cholesterol and triglycerides."

Overall, pecans are good for your overall health. However, they can be calorie-dense, so it's important to keep serving size in mind when snacking.

For this latest study, 68 grams of pecans were used in the shakes that provided potential cognitive benefits. At home, this would equate to a half cup of pecan halves, totaling 470 calories, 4.7g protein, 5g carbs, and 50g fat, which is a little high.

Nutritionists say an ideal snack serving size of pecans is about 1 ounce, or 19 pecan halves.