Instead of flashcards and multiplication drills to improve your child's school performance, you might want to focus on the family diet.

"Food can affect the brain in minutes," says neurologist Majid Fotuhi, chairman of the Neurology Institute for Brain Health and Fitness in Baltimore.

In fact, "the dietary habits of children can impact their energy level, mood and academic performance," says Megan Barna, an outpatient pediatric dietitian at Children's National Medical Center.

Fotuhi said nutrition "has a huge impact on brain function over years and over decades."

Fotuhi, also an assistant professor of neurology at Johns Hopkins University School of Medicine, said a poor diet has been linked directly to heart attack and stroke, as well as obesity, diabetes, high blood pressure, high cholesterol and inflammation.

"What you eat now - both the quantity and quality of food - can significantly impact long-term cognitive function and the risk of dementia and Alzheimer's disease later in life."

So what kinds of meals will help keep your family members' minds sharp, both immediately and over the long haul?

Fotuhi starts by recommending a Mediterranean-style diet that includes plenty of B vitamins along with antioxidant vitamins C and E, and Vitamin D.

He also emphasizes the importance of maintaining a good weight.

"Obesity can harm the brain in many different ways, such as reduced blood flow and increased risk of sleep apnea … and is also associated with a smaller-sized brain," which can affect short-term memory and risk of dementia, he said.

Fotuhi and Barna said DHA - an omega-3 fatty acid that is found in salmon, mackerel, trout, sardines, tuna and other fish - is the most important ingredient for brain health.

Some studies have shown that DHA supplementation can improve kids' memory, learning ability and cognitive performance, while low levels of DHA have been associated with increased risk for Alzheimer's and possible behavioral issues in children and adolescents.

Fotuhi said blueberries and spinach have also been associated with brain benefits such as enhanced cognitive and motor function. He said the evidence also is building for quinoa.

Fotuhi said most foods that are good for the mind also benefit cardiovascular health and your skin.