Older folks who eat fish a couple of times a week may be doing their brains a favor.
New research suggests that fish, even in moderate amounts, helps stave off vascular disease that may ultimately lead to dementia.
"Previous studies, including work from our team in France and others in the U.S., reported protective associations of eating fish against cognitive decline and risk of dementia in later life," study lead author Aline Thomas says.
Her new investigation found that among healthy adults aged 65 years or older, "two or more servings of fish per week may protect the brain against vascular lesions, before obvious signs of dementia appear," Thomas says.
There was one caveat, however: A protective effect was only seen among seniors younger than 75.
In the Nov. 3 issue of "Neurology", she and her colleagues reported the results of brain scans conducted among more than 1,600 men and women over 65 years old (average age 72). None of the participants had a prior history of dementia, stroke or heart disease.
RELATED: Easy Ways to Keep your Aging Mind Sharp
3 telltale signs of vascular illness
Scans were examined for three telltale signs of vascular illness. The scans revealed that small brain lesions were present in 2% of the patients, brain cavities were present in 8% and fluid build-up in brain tissue was present in 6%.
You May Also Like
Though all three can develop long before obvious signs of dementia, all have been linked to a long-term increased risk of dementia and an overall decline in mental acuity.
How much fish should you consume?
At the same time, participants were asked about their diets, and how much fish — including
salmon, tuna and/or sardines — they consumed each week.
On average, the group consumed fish about twice a week.
The research team then stacked the development of brain lesions, cavities and fluid up against each participant's fish consumption habits.
The result: Vascular disease — which can affect blood flow to the brain — was cited among just 18% who ate fish four times a week and in 23% of seniors under 75 who consumed fish three times weekly.
By contrast, nearly one-third of non-fish eaters had developed key markers for vascular illness.
The study authors stressed that their findings highlight an association, and do not actually prove that eating fish can prevent dementia onset.
RELATED: Could Your Hearing Loss Lead to Dementia?
Why isn't it effective for those over 75?
Still, why was no such association seen among those 75 and up?
"The reasons for this specificity are not clear yet," Thomas says. "One hypothesis is that fish consumption might be more beneficial at the earliest stages of the disease process, thus among younger participants."
Even so, she adds, if they hold up upon further research, the findings may ultimately provide "a potentially simple and
inexpensive preventive strategy" to help seniors get a head start on curbing dementia risk.
The findings make sense to Lona Sandon, program director of clinical nutrition in the school of health professions at UT Southwestern Medical Center, Dallas.
This is "not a surprise," Sandon says.
"The brain requires omega-3 fats found in salmon and sardines to develop and stay healthy throughout life," Sandon explains, noting brain tissue is made up of these healthy fats. "Omega-3s are just as important for brain health and promoting clear vessels in the brain as they are for heart health."
RELATED: This Diet Could Prevent Alzheimer’s Disease
Which fish is best for brain health?
The following fish are good sources of EPA (has anti-inflammatory affects), DHA (known for boosting brain health) and omega-3 fatty acids:
- Sardines
- Anchovies
- Mackerel
- Herring
- Rainbow trout
- Wild salmon
Eating these selections of fish will not only promote brain health, but can also protect you from type 2 diabetes, inflammation, autoimmune disease, and even depression. Additionally, consuming salmon twice a week is enough to cut your risk of heart attack, arrhythmia, stroke, high blood pressure, and triglycerides, according to functional medicine doctor Mark Hyman, MD.
On the other hand, he advises people to stay away from the following types of fish (or at least minimize your consumption):
- Tuna
- Swordfish
- King mackerel
- Catfish
- Chilean sea bass
- Tile Fish
These selections of fish tend to be higher in mercury.
It's not just seniors who stand to gain a significant health benefit, Sandon adds, stressing that "the need for healthy fats starts in infancy for proper growth and development of the brain."
Her take-home advice: "No need to wait. Start eating fish and other sources of omega-3s such as walnuts and flaxseed now. And to promote health and longevity with a sound mind, start early and eat fatty fish often."
