While there are still many questions surrounding the disease, including clear details on causes and prevention—or even what Alzheimer’s is in some cases—there is some general consensus on foods that seem to help prevent memory loss or assist with maintaining a sharper memory.

Blueberries: Studies have shown that diets rich in blueberries improved the learning and muscular function of aging rats. They also appear to protect the brain from damage caused by free radicals, which contributes to age-related diseases such as Alzheimer’s and dementia.

Dark chocolate: Dark chocolate contains flavonoids, compounds that have great antioxidant properties. In one study, scientists used mice that were genetically programmed to develop Alzheimer’s disease, and treated them with flavonoids. The results showed a reduced amount of harmful amyloid-beta brain deposits that are commonly found in Alzheimer’s patients.

Nuts and seeds: Nuts and seeds contain high volumes of vitamin E. In a study involving 6,000 participants from Chicago, those who consumed the most foods with vitamin E had a 67% lower risk of Alzheimer’s, compared to those who consumed the least amount of vitamin E from foods. As an antioxidant, vitamin E can combat the brain oxidation that causes mental deterioration, and subsequent memory loss.

Fish: The same Chicago study showed that those who ate fish at least once a week were 60% less likely to develop Alzheimer’s than those who rarely or never ate fish. Fatty fish, such as salmon and herring, have especially high levels of beneficial omega-3 fatty acids.

Whole Grains: A diet that is rich in whole grains can help lower your level of “bad” cholesterol, thereby reducing plaque build-up in the brain and enhancing blood flow to the body. In addition, whole grains are also good sources of vitamin E, mentioned earlier.

Beets: A study by scientists at Wake Forest University showed that when nitrates in beets are converted to nitric oxide in the body, they enhance blood flow, which can help brain health and prevent memory loss. The best way to consume this vegetable is freshly juiced or raw, as cooking it will deteriorate some of its nitrate value.

Eggs: Egg yolks contain choline, an essential nutrient that is a precursor for the neurotransmitter acetylcholine, which has an important role to play in memory. Alzheimer’s has been associated with acetylcholine deficiencies. Egg yolks also contain other healthy nutrients, like omega-3 fatty acid, folate, vitamin B12 and selenium. All of these are considered to be helpful in staving off Alzheimer’s.

While Alzheimer’s research is making continual advances, there are still questions around causes and treatments. Eating a healthy diet that includes these foods can be a strong preventative step.