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Brain Health and Fish

Contributors: Sarah Klemm, RDN, CD, LDN

Reviewers: Academy Nutrition Information Services Team

Published: June 06, 2022

Reviewed: February 19, 2024

Brain Health and Fish
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When is the last time you had fish for dinner? If you can't remember, it may be more than the passage of time that's to blame. Research suggests that improved memory is just one of many brain-boosting benefits associated with eating more fish.

You Are What You Eat

You've likely heard that omega-3 fatty acids are good for your health. But one in particular, docosahexaenoic acid, or DHA, goes straight to your head. DHA is an omega-3 fatty acid that is required to keep the brain functioning normally and efficiently. Brain and nervous system tissues are partly made up of fat, and research suggests they have a special preference for DHA over other types of fatty acids.

If you think higher levels of DHA in your diet might simply help you remember to put fish on your shopping list, keep in mind that several studies have linked DHA deficiencies to more serious cognitive problems than occasional forgetfulness. In fact, low levels of DHA have been associated with a greater risk of Alzheimer's disease in later years.

Signs of memory loss shouldn't be your first signal to boost intake. Think of fish consumption as a savings plan for your brain, not a winning lottery ticket. Long-term consumption of adequate DHA is linked to improved memory and reduced rates of cognitive decline. To reap the brain benefits of DHA, you need to maintain a consistent intake of DHA-rich foods.

Sea-Worthy Servings

Do you have to be swimming in fish dinners to feed your brain? The 2020-2025 Dietary Guidelines for Americans recommends adults consume at least 8 ounces of seafood per week. This works out to be two 4-ounce servings of fish. Oily fish such as salmon, tuna, Atlantic mackerel, herring and trout are great catches with DHA to offer. When you get cooking, think broiling or grilling — the extra fat from deep-frying is counterproductive when there's lean protein on the menu. Choose varieties that are lower in mercury levels more often, such as salmon or freshwater trout. Meanwhile, shark and swordfish are choices to limit due to high mercury levels. You also can select fish that have a lesser environmental impact — consider varieties that have been certified for responsible seafood production.

Brains and Brawn

Add one more plus to the fish list: lean protein. To make sure the body stays in top aerobic condition to power through exercise, the effect of fish on the heart is just one more benefit. Aside from being lower in saturated fat than red meat, swapping burgers for tuna means more omega-3s, which studies suggest may reduce the risk for heart disease.<

Seafood or Seaweed?

For people who follow a vegetarian or vegan diet, all is not lost — getting DHA is possible. Algae is a primary source of DHA and is used to make vegetarian DHA supplements. Ground flaxseed, walnuts and chia seeds are other plant-based sources of another omega-3 fatty acid, ALA, which the body converts into DHA. However, our bodies may convert less than 15% of ALA to DHA. If your primary intake of omega-3s comes from sources other than oily fish, consider speaking to a doctor or registered dietitian nutritionist about supplementation.

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