Previously I posted about studies showing regular fish oil supplements could help ward off dementia.

The Atlantic in a “This is Your Brain on Fish” by James Hamblin covers the evidence that regular consumption of baked or broiled fish having similar positive effects on brain tissue and functioning:

Dr. Cyrus Raji, a resident radiologist at UCLA, appreciates value beyond the cosmetics of a thick cerebral cortex. He’s the lead researcher in a new study in the current American Journal of Preventive Medicine that found that people who regularly eat fish have more voluminous brains than those who do not—in such a way that stands to protect them from Alzheimer’s disease.

“Understanding the effects of fish consumption on brain structure is critical for the determination of modifiable factors that can decrease the risk of cognitive deficits and dementia,” Raji and colleagues write. The team has previously shown gainful effects of physical activity and obesity on brain structure.

This study found that eating fish—baked or broiled, never fried—is associated with larger gray matter volumes in brain areas responsible for memory and cognition in healthy elderly people.

“There wasn’t one type of fish that was the best,” Raji told me by phone, probably while eating fish. “All that mattered was the method of preparation.” Fried fish had a unique dearth of benefits to the brain.

People who eat fish at least once a week have larger gray matter volumes in the red/yellow areas. “If you eat fish just once a week, your hippocampus—the big memory and learning center—is 14 percent larger than in people who don’t eat fish that frequently. 14 percent. That has implications for reducing Alzheimer’s risk,” Raji said. “If you have a stronger hippocampus, your risk of Alzheimer’s is going to go down.”

“In the orbital frontal cortex, which controls executive function, it’s a solid 4 percent,” Raji said. “I don’t know of any drug or supplement that’s been shown to do that.”

Speaking of supplements, the researchers initially looked to omega-3 fatty acids as the driver of these benefits. But when they looked at the levels of omega-3s in people’s blood, they didn’t correlate with better brain volumes.

“These findings suggest additional evidence that it is lifestyle factors—in this case, dietary intake of fish,” the researchers write, “and not necessarily the presumed biological factors that can affect the structural integrity of the brain.”

Omega-3 fatty acids have previously been shown to slow cognitive decline. In one study, higher levels of omega-3 fatty acids in people’s blood were associated with lower rates of brain atrophy observable over just a four-year period. We also know that when rats are fed diets low in omega-3 fatty acids, they have increased signs of dementia, possibly mediated by insulin and related buildup of amyloid plaques in their tiny brains.

Eating more omega-3 fatty acids, a lot of fruit, and not much meat, has previously been associated with increased volume throughout the brain’s gray matter. Recent research in the journal Neurology found that elderly people with high levels of omega-3 fatty acids in their blood had better cognitive function than those with lower levels. MRIs of their brains showed larger volumes, too. (The associations also held for vitamins B1, B2, B6, B12, C, D, and E, and folate.)

Drs. Deborah Barnes and Kristine Yaffe at UCSF recently calculated in Lancet Neurology that up to half of cases of Alzheimer’s disease “are potentially attributable” to seven modifiable risk factors: diabetes, midlife high blood pressure, midlife obesity, smoking, depression, cognitive inactivity or low educational attainment, and physical inactivity. Minimal inroads in those areas, they say, could result in millions fewer cases of Alzheimer’s.

People who ate fish once per week were just as well off as those who ate it more frequently.
Researchers at the University of Pittsburgh School of Medicine corroborate, “Our research has consistently shown that it is the interactions among these risk factors with the patho-biological cascade of Alzheimer’s disease that determine the likelihood of a clinical expression as dementia or mild cognitive impairment.”

Specific suspects in the fish-brain benefit paradigm are omega-3s docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which seem to increase the size of the amygdala and anterior cingulate gyrus, and possibly overall brain volume. DHA and EPA can also affect the way neural synapses fire.

I have a can of Costco salmon filet every day for lunch; it’s an easy, delicious way to both meet protein needs and consume the healthy fish oils that protect and increase brain power.

Fish Oil Supplements Ward Off Dementia

For more on good supplements and life-extending habits:

Getting to Less Than 10% Body Fat Like the Models – Ask Me How!
Low-Dose Aspirin Reduces Pancreatic Cancer
Daily Aspirin Regimen Reduces Cancer Rates
Almonds: Superfood, Eat Them Daily for Heart Health
Fish Oil Supplements Ward Off Dementia
Lower Back Pain: Acetaminophen (Tylenol, Paracetamol) Useless
Cleanses and Detox Diets: Quackery
Gluten-Free Diets: The Nocebo Effect
Scams: Multi-Level Marketing, Herbalife
Vitamin D: Anti-Dementia?
Salt: New Research Says Too Little May Be Unhealthy