When Dr. Kellyann Niotis began studying neurology, she remembers learning how to manage diseases like Alzheimer’s and dementia.

It was the lack of information about how prevent them that I couldn’t understand.

“My family has been affected by neurodegenerative diseases, and I have seen countless patients suffer from these diseases,” Niotis, a preventive neurologist and assistant professor of neurology at Weill Cornell Medicine, told Business Insider. “What strikes me most is that the disease doesn’t just affect that person; it really affects everyone.”

Niotis was inspired to specialize in preventive neurology when she discovered that lifestyle advice was lacking. “It was heartbreaking for me to hear, over and over again, doctors say that nothing can be done or just give generic health advice that has no real concreteness or link to neurology.”

While diet and exercise are linked to better brain health, Niotis wanted to get more granular. What foods were the best and why? Are some exercises better than others?

Niotis, who spent the last decade in the field of neurology, shared some of his own habits for reducing his risk of Alzheimer’s, based on what he learned from his research.

The staples of their diet are berries, fatty fish and plenty of water.

Niotis said most Americans don’t drink enough water or realize how important hydration is for brain health.

“Our brains are made primarily of fat and water,” he said. “Even mild levels of dehydration can cause problems with concentration, attention, and feelings of brain fog.”

Niotis always carries a large water bottle with markings so he can visually track how much water he has drunk in a day.

When it comes to his diet, he only has a few strict guidelines. “I eat berries every day,” he said. “That’s one of my rules of life.” Berries are rich in polyphenols and other antioxidants that can help reduce oxidative stress and inflammation. Some observational studies have linked higher berry consumption to slower cognitive decline.

Also try to eat fatty fish, such as salmon, sardines, mackerel and anchovies, twice a week. “They’re the ones that typically smell the most, so they’re less appetizing to a lot of people,” Niotis said. “But I really try to do that.”

Fatty fish have higher levels of omega-3 fatty acids like DHA and EPA, which help keep brain cell membranes healthy and can also reduce inflammation.

Intense strength training appears to reduce risk of neurodegeneration

Niotis typically works out four to five times a week, opting for a combination of strength training and cardio.

The former, he said, is especially important for brain health. Women, who tend to lose more muscle mass than men on average, are especially at risk of developing sarcopenia, an age-related loss of muscle mass that is linked to neuromuscular degeneration.

Skeletal muscle and the brain communicate through metabolic and signaling pathways. In some studies, lower muscle mass has been associated with smaller hippocampal volume and worse cognitive outcomes.

Sometimes the risks can be more direct: Low muscle mass increases the risk of falls and subsequent brain injuries when you’re older, Niotis said. This inspired her to add more strength training to her exercise routine.

Still, he said it took him time to get used to lifting more weight. “When I started, I did very easy machine circuits in the gym because I didn’t really know much about gaining muscle mass and I was very worried about injuring myself,” she said. You would do more reps with less weight, which you now know is not as helpful for building or maintaining muscle.

Instead, your goal is to perform six to 10 repetitions of a heavier weight for three to four sets to progressively overload and more effectively increase your muscle mass.

Adding variety to your routine stimulates your brain

In general, Niotis tries to provide variety whenever it can.

“The brain loves novelty,” he said. “Any time you challenge your brain to do different things is a benefit.”

An easy way to do this is by changing your cardio exercises, from running to rowing to cycling. Whatever you do, opt for short bursts of intensity where you hit a target heart rate of about 85% (or a zone 4 heart rate) for up to two minutes before recovering.

In addition to the fact that good heart health helps improve blood flow to the brain, he said getting out of your comfort zone can help increase brain reserve. “After exercise, I feel like my brain is very alert,” he said.

He also tries to replicate that acuity in other parts of his life. He said interacting with lots of different people, whether at work or socially, also adds novelty.

“Every time you talk to someone, you’re exposed to new thoughts, new ideas, new language,” he said. “This in itself provides connectivity, which can also help the brain.”