Why You Should Eat More Fatty Fish for Brain Health as You Age

Protein is best known for helping us build healthy muscles, but its nutrients offer benefits from head to toe. In particular, protein plays an important role in the health of your brain, and getting enough of the right amount in your diet can help maintain its function.

Protein is found in every cell of the body including the brain, so it’s important to get enough of it through your diet. That said, of all the protein-rich foods out there, some may benefit your brain more than others.

As for which proteins best support your brain, we asked a neurologist who told us that you can support your cognitive function over the years by adding more fatty fish to your routine. This is why.

Fatty fish, which include salmon, black cod, anchovies and bluefin tuna, are high in protein and other nutrients such as omega-3 fatty acids (a type of “healthy fat”), making them a nutritious addition to any diet.

For example, a 6-ounce filet of cooked salmon provides 43.2 grams of protein and 246 percent of your Daily Value (DV) for omega-3 fatty acids, according to the USDA.

With input from Sharon Stoll, DO, neurologist and Assistant Professor of Neurology at Yale School of Medicine, we dive into how eating fatty fish regularly can support healthy cognition.

The brain is made up of about 60 percent fat, so it’s an essential nutrient for brain function, according to John Hopkins Medicine. But some forms may be better than others.

Docosahexaenoic acid, or DHA, is an omega-3 fatty acid commonly associated with brain function, although it also supports a healthy nervous system.

Fish is an ideal source of DHA because it is readily available. In fact, most of the main food sources of DHA are fatty fish such as salmon, tuna and cod, according to the USDA. Plant sources of omega-3 fatty acids contain alpha-linolenic acid (ALA), which is converted to DHA in the body.

Brain tissue may have a preference for DHA to keep the brain functioning normally and efficiently, according to the Academy of Nutrition and Dietetics.

DHA is especially important for brain development in early childhood, according to the Harvard TH Chan School of Public Health. Although its effects are primarily seen in infants, the effects of DHA can also be seen during childhood and adulthood, according to a January 2016 review in ‌Nutrients.

In adulthood, low levels of DHA have been linked to a higher risk of brain conditions such as Alzheimer’s dementia.

The body is made up of complex systems, and they do not function independently of each other. The function of your cardiovascular system, for example, can affect the health of your brain.

“A lot of people don’t realize how interconnected the heart and brain are — you can’t have one without the other,” Stoll said. “Healthy fats are as important for brain health as they are for the cardiovascular system, which then plays a role in brain function.”

Keeping your heart healthy can reduce your risk for brain-related health problems like stroke and dementia, according to the CDC. When blood vessels are damaged, your brain can face serious consequences.

“To keep your brain in really good shape, we want the blood vessels to open as wide as possible,” Stoll said. That’s where nutrient-dense foods like fatty fish come in.

Protein is an important nutrient, but animal protein such as pork and some cuts of beef are high in saturated fat, which can raise the level of “bad” cholesterol in your blood and clog your arteries. This increases your risk for stroke and heart attack, according to the American Heart Association (AHA).

Fish is considered a more heart-healthy source of protein because it is not high in saturated fat. In fact, omega-3 fatty acids can actually improve endothelial function (the lining of your blood vessels), promote vasodilatation (widening of blood cells) and reduce arterial wall stiffness, according to a March 2017 research in ‌Nutrition, Metabolism and Cardiovascular Disease.

Keeping your heart healthy, then, translates to better blood flow to your brain.

Much remains to be learned about Alzheimer’s disease, the most common type of dementia, but high triglyceride levels may play a role.

“Eating fatty fish is important for brain health for the same reason it’s important for the heart — it’s associated with lower triglyceride levels,” Stoll said. It’s true: High triglyceride levels in midlife are linked to a higher risk of Alzheimer’s disease later in life, according to a January 2018 study in ‌Neurology.

“Triglycerides are part of what blocks those channels in the brain and throughout the body, which leads to stroke and heart disease,” Stoll said. There is strong evidence that omega-3 fatty acids can help lower high triglyceride levels, according to the Mayo Clinic.

As the number of older adults (age 65+) increases, so do rates of dementia and Alzheimer’s disease diagnoses. An estimated 5.8 million people in the United States are affected by the disease, although that number is expected to rise in the coming years, according to the CDC.

Getting more DHA has been linked to a lower risk of this disease, according to a June 2022 study in ‌Nutrients. Low levels of DHA have also been linked to a higher risk. That being said, more research is needed to determine the direct benefits DHA may have on cognition.

“Although the research is inconclusive, one thing is certain – nutrients like omega-3 fatty acids can help protect your brain over time and can slow the progression of brain diseases,” Stoll said.