Short answer: Yes, with moderate evidence. Salmon is one of the richest food sources of DHA, an omega-3 fat that is a major building block of the brain. People with higher DHA levels or fish intake have lower dementia risk in observational studies. One DHA supplement trial improved memory, but a larger omega-3 trial did not. Eat 2-3 servings a week.

Salmon is good for the brain, with moderate evidence. Higher DHA levels and fish intake are linked to better cognition, larger brains and lower dementia risk, but supplement trials are mixed.

How much salmon to eat

  • 2-3 servings of fatty fish a week: Salmon is an excellent choice; sardines are another.
  • Serving size: 85-115 g cooked, about the size of a deck of cards.
  • Wild or farmed: Farmed Atlantic salmon has as much DHA as wild Atlantic and more than most wild Pacific species. Wild salmon has less omega-6 fat.
  • Canned salmon with bones: A cheaper option that also provides calcium.

For ideas, try wild salmon with blueberry salsa or an omega-3 power bowl.

Nutrients in a 115 g cooked serving

Omega-3 content varies a lot by species (USDA figures):

NutrientAmount per serving
DHA0.5-1.7 g: about 1.6-1.7 g in Atlantic (wild or farmed), 0.6-0.8 g in sockeye or coho, 0.5 g in pink
EPA0.25-1.2 g, depending on species
Vitamin Dabout 600-770 IU in sockeye, pink and farmed Atlantic
Vitamin B12about 3-5.5 mcg
  • DHA: The main omega-3 fat in brain structure.
  • Vitamin B12: Needed for healthy myelin, the insulation around nerves, and for nerve signaling.
  • Selenium: A trace mineral with antioxidant roles in the brain.
  • Protein: Provides the amino acids the brain uses to make chemical messengers.

Dementia risk and brain size

In the Framingham Heart Study (Schaefer 2006), 899 older adults were followed for about 9 years. Those in the top quarter of blood DHA levels had a 47% lower risk of dementia than the rest. People in the top quarter ate about 3 servings of fish a week on average. This is an observational finding and can’t show that DHA or fish caused the lower risk.

An MRI study of 1,111 postmenopausal women (Pottala 2014) found that those with higher omega-3 levels (EPA + DHA) in red blood cells 8 years earlier had larger brains. Their hippocampus, the memory center that usually shrinks first in Alzheimer’s disease, was also larger. Each standard deviation of higher omega-3 level was linked to about 2.1 cubic centimeters more brain volume. This measured blood levels, not intake, and was observational.

Supplement trials

In the MIDAS trial (Yurko-Mauro 2010), 485 healthy adults aged 55 and over with mild memory complaints took 900 mg/day of algae-based DHA or a placebo for 24 weeks. DHA improved the main outcome, a test of visual learning and memory, but not working memory or executive function. This used supplements, not fish.

The larger AREDS2 trial (Chew 2015) gave about 3,500 older adults 1 g/day of omega-3s or a placebo for 5 years. It found no effect on cognitive decline. More on doses and forms in our omega-3 guide.

Mood and depression

Trials of omega-3 supplements for depression have mixed results. A 2011 meta-analysis (Sublette 2011) found that supplements in which EPA made up at least 60% of the omega-3s reduced depression scores in people with depression. Doses were 200-2,200 mg/day of EPA in excess of DHA. DHA-heavy supplements had no effect. These were supplement trials, not salmon, and supplements are not a substitute for depression treatment.

Who should be careful

  • Pregnancy: Choose low-mercury fish. Salmon is one of the safest options, along with sardines and anchovies.
  • Mercury: Minimal with salmon, which is on the FDA’s “best choices” list of low-mercury fish.
  • Blood thinners: Keep your vitamin K intake steady. Salmon is not a high-K food, but consistency matters.
  • Gout: You may need to eat less purine-rich fish during flare-ups.
  • Fish oil supplements: If you take them instead of eating fish, they can increase bleeding risk with anticoagulants or antiplatelet drugs. In a meta-analysis of trials (Gencer 2021), doses above 1 g/day were linked to a higher risk of atrial fibrillation. Ask a doctor or pharmacist first, and see our fish oil guide.

Sources

  • Chew, E. Y., et al. (2015). Effect of omega-3 fatty acids, lutein/zeaxanthin, or other nutrient supplementation on cognitive function: The AREDS2 randomized clinical trial. JAMA, 314(8), 791–801. doi:10.1001/jama.2015.9677
  • Gencer, B., Djousse, L., Al-Ramady, O. T., Cook, N. R., Manson, J. E., & Albert, C. M. (2021). Effect of long-term marine ω-3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: A systematic review and meta-analysis. Circulation, 144(25), 1981–1990. doi:10.1161/CIRCULATIONAHA.121.055654
  • Pottala, J. V., Yaffe, K., Robinson, J. G., Espeland, M. A., Wallace, R., & Harris, W. S. (2014). Higher RBC EPA + DHA corresponds with larger total brain and hippocampal volumes: WHIMS-MRI study. Neurology, 82(5), 435–442. doi:10.1212/WNL.0000000000000080
  • Schaefer, E. J., et al. (2006). Plasma phosphatidylcholine docosahexaenoic acid content and risk of dementia and Alzheimer disease: The Framingham Heart Study. Archives of Neurology, 63(11), 1545–1550. doi:10.1001/archneur.63.11.1545
  • Sublette, M. E., Ellis, S. P., Geant, A. L., & Mann, J. J. (2011). Meta-analysis of the effects of eicosapentaenoic acid (EPA) in clinical trials in depression. The Journal of Clinical Psychiatry, 72(12), 1577–1584. doi:10.4088/JCP.10m06634
  • Yurko-Mauro, K., et al. (2010). Beneficial effects of docosahexaenoic acid on cognition in age-related cognitive decline. Alzheimer’s & Dementia, 6(6), 456–464. doi:10.1016/j.jalz.2010.01.013
  • USDA FoodData Central, SR Legacy: salmon, cooked, dry heat (Atlantic wild 171998, Atlantic farmed 175168, sockeye 173692, coho wild 173719, pink 172001, chinook 171999). fdc.nal.usda.gov