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Category: brain

Published on Leave a comment on Brains of Teen Football Players Don’t Fully Heal During the Off Season

This past week there was discussion of the number of high school football players that die annually while playing football (at least 5). But the bigger risk - because it involves so many players - is the damage to brains that occurs from concussions and from just being hit in football. The response from football enthusiasts is that there are safeguards now - that football players don't play after a concussion until they "heal" (show no obvious symptoms). But do they really heal? And much of the damage is from repeated hits, without having a concussion (sub-concussive blows or hits), what about the damage from that?

This study found that repeated head hits in football can cause changes in brain chemistry and metabolism, even in high school players not diagnosed with concussions. And even after the lengthy off-season (somewhere between two and five months after the season has ended)—the majority of players are still showing that they had not fully recovered. The researchers also made it clear that 2 weeks is not enough time to heal from a concussion. Scary long-term implications - what is happening to brains that never truly heal from past seasons as the players start playing in the next season? From Futurity:

High School Football: Teen Brains Don't Heal During Offseason

Brain scans of high school football players taken before, during, and after the season raise concerns they don’t fully recover from repeated head hits. The researchers used an imaging technique called proton magnetic resonance spectroscopy (1H MRS) to study the brains of 25 high school football players and compared them to the brains of teenagers involved in non-contact sports. The findings suggest repeated head hits in football can cause changes in brain chemistry and metabolism, even in players not diagnosed with concussions. 

“We are seeing damage not just to neurons, but also to the vasculature and glial cells in the brain,” says Eric Nauman, professor of mechanical engineering, basic medical sciences, and biomedical engineering at Purdue University. “I was particularly disturbed that when you get to the offseason—we are looking somewhere between two and five months after the season has ended—the majority of players are still showing that they had not fully recovered.”

The 1H MRS data provide details about the blood flow, metabolism, and chemistry of neurons and glial cells important for brain function. The data also revealed a “hypermetabolic response” during the preseason, as though the brain was trying to heal connections impaired from the previous season. “We found that in the preseason for the football players in our study, one part of the brain would be associating with about 100 other regions, which is much higher than the controls,” says Thomas Talavage,  professor of electrical and computer engineering and biomedical engineering and co-director of the Purdue MRI Facility.

“The brain is pretty amazing at covering up a lot of changes. Some of these kids have no outward symptoms, but we can see their brains have rewired themselves to skip around the parts that are affected.”

One of the research papers shows that knowing a player’s history of specific types of hits to the head makes it possible to accurately predict “deviant brain metabolism,” suggesting that sub-concussive blows can produce biochemical changes and potentially lead to neurological problems, which indicates a correlation between players taking the heaviest hits and brain chemistry changes.

The data shows that the neurons in the motor cortex region in the brains of football players produced about 50 percent less of the neurotransmitter glutamine compared to controls. “We are finding that the more hits you take, the more you change your brain chemistry, the more you change your brain’s ability to move blood to the right locations,” Nauman says.

“Recent proton magnetic resonance spectroscopy studies argue that the recommended two-week window of rest is insufficient for full metabolic recovery after concussion,” Nauman says. “Those returning to play prior to full recovery could incur a second concussion with symptoms and metabolic changes more lasting than the first.”

Published on Leave a comment on Drink Coffee and Live Longer?

 Drink coffee daily -  3 to 5 cups of either regular or decaffeinated - and live longer by lowering your risk of premature death from cardiovascular disease, neurological disease, type 2 diabetes, and suicide. Yes, it was an observational study, but the results are similar to what other studies are finding. From Medical Xpress:

Moderate coffee drinking may lower risk of premature death

People who drink about three to five cups of coffee a day may be less likely to die prematurely from some illnesses than those who don't drink or drink less coffee, according to a new study by Harvard T.H. Chan School of Public Health researchers and colleagues. Drinkers of both caffeinated and decaffeinated coffee saw benefits, including a lower risk of death from cardiovascular disease, neurological diseases, type 2 diabetes, and suicide.

"Bioactive compounds in coffee reduce insulin resistance and systematic inflammation," said first author Ming Ding, a doctoral student in the Department of Nutrition. "That could explain some of our findings. However, more studies are needed to investigate the biological mechanisms producing these effects."

Researchers analyzed health data gathered from participants in three large ongoing studies: 74,890 women in the Nurses' Health Study; 93,054 women in the Nurses' Health Study 2; and 40,557 men in the Health Professionals Follow-up Study. Coffee drinking was assessed using validated food questionnaires every four years over about 30 years. During the study period, 19,524 women and 12,432 men died from a range of causes.

In the whole study population, moderate coffee consumption was associated with reduced risk of death from cardiovascular disease, diabetes, neurological diseases such as Parkinson's disease, and suicide. Coffee consumption was not associated with cancer deaths. The analyses took into consideration potential confounding factors such as smoking, body mass index, physical activity, alcohol consumption, and other dietary factors.

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Could this be? Fungal infection being the cause of Alzheimer's disease? Noteworthy from a recent study conducted in Spain: all the Alzheimer's disease (AD) patients had evidence of fungal infections in their brains, central nervous systems, and vascular systems, but none were found in the control subjects (those without Alzheimer's disease). Many of the symptoms of AD (such as inflammation of the central nervous system and activation of the immune system) match those with long-lasting fungal infections. A "microbial cause" has long been suggested as a cause of AD, and interestingly other studies have also found fungal infections in AD patients. The research so far has found several fungal species in AD patients (including Candida albicans). The researchers mention that in one study anti-fungal treatment reversed clinical symptoms of AD in 2 patients (but it was written off  as misdiagnosis).

Another possibility that immediately occurs to  explain the findings is that perhaps Alzheimer's disease somehow results in fungal infections - that the AD makes them more prone to fungal infection. In case you're wondering - all the AD patients and control patients studied had died - this is why their brain tissue could be studied so thoroughly. Excerpts from a research article by D. Pisa et al in Nature:

Different Brain Regions are Infected with Fungi in Alzheimer’s Disease

The possibility that Alzheimer’s disease (AD) has a microbial aetiology has been proposed by several researchers. Here, we provide evidence that tissue from the central nervous system (CNS) of AD patients contain fungal cells and hyphae. Fungal material can be detected both intra- and extracellularly using specific antibodies against several fungi. Different brain regions including external frontal cortex, cerebellar hemisphere, entorhinal cortex/hippocampus and choroid plexus contain fungal material, which is absent in brain tissue from control individuals. Analysis of brain sections from ten additional AD patients reveals that all are infected with fungi. Fungal infection is also observed in blood vessels, which may explain the vascular pathology frequently detected in AD patients. Sequencing of fungal DNA extracted from frozen CNS samples identifies several fungal species. Collectively, our findings provide compelling evidence for the existence of fungal infection in the CNS from AD patients, but not in control individuals.  ...continue reading "Fungal Infections Involved in Alzheimer’s Disease?"

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Another study providing evidence that the Mediterranean diet is good for the brain. In elderly dementia-free adults (mean age 80 years) - those that generally followed a Mediterranean diet (higher adherence) had a larger brain volume than those not following the Mediterranean diet, as well as more total gray and white matter volume.The difference between the groups is equal to about 5 years of aging.

Having "higher adherence to the Mediterranean diet" in the study meant higher consumption of healthy foods or lower consumption of unhealthy foods. The Mediterranean diet stresses a  high intake of vegetables, legumes, fruits, whole grains, fish, olive oil, and low intake of saturated fatty acids, dairy products, meat, and poultry; and mild to moderate amounts of alcohol. Specifically: Higher fish intake (at least 3 to 5 oz. weekly) and lower meat intake (no more than 3.5 oz. daily) correlated with greater total gray matter volume. Higher fish intake was also associated with "greater mean cortical thickness". From Medical Xpress:

Mediterranean diet may keep your mind healthier in old age

In news that sounds a bit like it came straight from a sci-fi thriller, researchers say that eating too much meat might shrink your brain. On the flip sid e, however, eating healthy foods from the so-called Mediterranean diet may help your brain stay in good shape as you get older, the new study suggests. The researchers said that people over 65 who ate more fish, vegetables, fruit, grains and olive oil had a larger brain volume than a similar group who didn't follow a Mediterranean diet.

"It was encouraging to see that the more you adhere to this Mediterranean diet, the more protection you get against brain atrophy [shrinkage]," said study author Yian Gu, an assistant professor of neuropsychology at Columbia University in New York City. .... But Gu noted that her study's observational findings cannot prove a definitive cause-and-effect relationship between diet and brain volume. The study was only designed to find an association.

Previous research has linked the Mediterranean diet to a lower risk of Alzheimer's disease, the study said. The diet stresses the consumption of vegetables, legumes (beans, peas and lentils), fruits, cereals, fish and monounsaturated fats such as olive oil, the study authors said. The eating plan also includes a low intake of meat, poultry, saturated fats and dairy products, as well as mild to moderate amounts of alcohol, according to the researchers.

For the study, Gu and her colleagues split 674 adults into two groups based on how closely their diets aligned with the Mediterranean diet. Their average age was 80 years. All participants underwent MRI scans of their brains to measure total brain volume and thickness. They also completed questionnaires about their food choices and eating patterns.

The researchers found that brain volumes of those who didn't follow a Mediterranean diet were smaller than those who did. The difference was minor in overall size—equated to about five years of aging, the study authors said. But, more specifically, the investigators found that eating more fish and less meat was associated with even less brain shrinkage. Using the study findings, Gu contended that eating at least 3 to 5 ounces of fish weekly, or no more than 3.5 ounces of meat each day, could protect the brain from shrinkage. She acknowledged that study participants may have inaccurately recalled their food consumption habits in the questionnaires used.

Published on Leave a comment on Shrink Your Brain With An Unhealthy Diet

Over and over studies find that a person's diet is linked to health and diseases, and now a study finds that an unhealthy diet is linked to shrinkage of the brain, specifically the volume of the left hippocampus. The biggest effects on the hippocampus are found with both greater consumption of an unhealthy diet and lower consumption of a healthy diet.  The hippocampus is a brain structure associated with both learning and memory, as well as mood regulation, and is specifically implicated in depression. In dementia and Alzheimer's disease, the hippocampus is one of the first regions of the brain to suffer damage.

So....you want to protect your hippocampus from shrinkage. The researchers themselves  suggest that the effects may be reversible, and suggest "dietary interventions to promote hippocampal health". Once again, a healthy diet means lots of plant-based foods (for example, a Mediterranean based diet with lots of fruits, vegetables, legumes, nuts, berries, seeds), and decreasing a Western-style diet with highly processed foods, low fiber, lots of meat, fat,  and refined sugars. From Medscape:

Unhealthy Diet May Shrink the Brain

Consumption of an unhealthy Western diet characterized by meat, hamburgers, chips, and soft drinks, may reduce the volume of the left hippocampus, whereas a healthy diet of fresh vegetables and fish may increase hippocampal volume. In a study of more than 250 individuals, investigators found that during a period of 4 years, there was a difference of more than 200 cubic millimeters in hippocampal volume between individuals who ate a healthy diet and those who consumed an unhealthy diet.  ...continue reading "Shrink Your Brain With An Unhealthy Diet"

Published on Leave a comment on Low Vitamin D Levels Associated With Cognitive Decline Among Older Adults

New research has found that low vitamin D levels among older adults is associated with accelerated cognitive decline and impaired performance (particularly in areas of memory and executive function). The next research in this area will have to look at whether vitamin D supplementation will change (slow down) the decline. Please note that it is widely accepted that an average daily intake of 1000 IU  of D3 daily is safe. The best source of  vitamin D is sunlight. From Science Daily:

Low vitamin D among elderly associated with decline in cognition, dementia

Vitamin D insufficiency among the elderly is highly correlated with accelerated cognitive decline and impaired performance, particularly in domains such as memory loss that are associated with Alzheimer's disease and dementia, researchers with the UC Davis Alzheimer's Disease Center and Rutgers University have found. The effect is "substantial," with individuals with low vitamin D declining at a rate three times faster than those with adequate vitamin D levels. 

The researchers said their findings amplify the importance of identifying vitamin D insufficiency among the elderly, particularly high-risk groups such as African-Americans and Hispanics, who are less able to absorb the nutrient from its most plentiful source: sunshine. Among those groups and other darker-skinned individuals, low vitamin D should be considered a risk factor for dementia, they said. "Independent of race or ethnicity, baseline cognitive abilities and a host of other risk factors, vitamin D insufficiency was associated with significantly faster declines in both episodic memory and executive function performance," said Joshua Miller...

The large, longitudinal study was conducted in nearly 400 racially and ethnically diverse men and women in Northern California participating in longitudinal research at the Alzheimer's Disease Center in Sacramento, Calif. Fifty percent of participants were Caucasian and 50 percent were African-American or Hispanic. The participants had a mean age of 76 and were either cognitively normal, had mild cognitive impairment, or dementia.The participants' serum vitamin D status was measured at the beginning of the study.... Overall, 26 percent were deficient and 35 percent were insufficient. Among Caucasians, 54 percent had low vitamin D, compared with 70 percent of African-Americans and Hispanics.

Over five years of follow-up, vitamin D deficient individuals experienced cognitive declines that were two-to-three times faster than those with adequate serum vitamin D levels. In other words it took only two years for the deficient individuals to decline as much as their counterparts with adequate Vitamin D declined during the five-year follow-up period.

Exposing the skin to sunlight is the major source of vitamin D. Racial and some ethnic minorities are at greater risk of low vitamin D because the higher concentration of melanin that makes their skin darker -- and protects against skin cancer in sunny climates -- also inhibits synthesis of vitamin D. Diet is the other major source of vitamin D. Dietary vitamin D is obtained particularly through dairy consumption. The intake of dairy products is especially low among minority groups, with only 6.5 percent of African-Americans and 11 percent of Mexican-Americans nationwide consuming the recommended three daily servings of dairy products, the study says.

Published on Leave a comment on Coffee Appears To Have Lots of Health Benefits

A nice summary article about the benefits and risks of coffee consumption. Summary of effects of drinking coffee: 1) May potentially increase blood pressure, but also may lower the risk for coronary disease, and protect against heart disease. 2) May cut stroke risk by as much as 25%, 3) Linked to  improved glucose metabolism, reduced risk for type 2 diabetes, and promotion of weight loss in overweight patients. 4) May reduce the risk for several cancers. 5) Appears to slow the progression of dementia and Parkinson's disease. 6) A significantly decreased risk of developing depression. 7) Slows progression in alcoholic cirrhosis, hepatitis C, and NAFLD (non-alcoholic fatty liver disease). 8) May be beneficial in dry-eye syndrome, gout, and in preventing MRSA infection. 9) May increase blood pressure, anxiety, insomnia, tremor, withdrawal symptoms, and potential increased risk of glaucoma. From Medscape:

How Healthy Is Coffee? The Latest Evidence

Earlier this year, the Dietary Guidelines Advisory Committee (DGAC) released a report[1] stating that up to five cups of coffee per day, or up to 400 mg of caffeine, is not associated with long-term health risks. Not only that, they highlighted observational evidence that coffee consumption is associated with reduced risk for several diseases, including type 2 diabetes, cardiovascular disease (CVD), and neurodegenerative disorders. The body of data suggesting that moderate coffee—and, in all likelihood, tea—consumption is not only safe but beneficial in a variety of mental and medical conditions is growing fast.

A 2012 study of over 400,000 people, published in the New England Journal of Medicine, reported that coffee consumption is associated with a 10% reduction in all-cause mortality at 13-year follow-up.... It's important to note that much of the evidence on the potential health effects of coffee, caffeine, and other foods and nutrients is associational and doesn't prove causality—observational investigations come with limitations and often rely on error-prone methods such as patient questionnaires. However, the sheer volume of existing observational data linking coffee and/or caffeine with various health benefits—as well as, in many cases, evidence of a dose response—suggests that the most widely consumed stimulant in the world has positive influences on our health. 

Cardiovascular Disease:...However, when caffeine is ingested via coffee, enduring blood pressure elevations are small and cardiovascular risks may be balanced by protective properties. Coffee beans contain antioxidant compounds that reduce oxidation of low-density lipoprotein (LDL) cholesterol, and coffee consumption has been associated with reduced concentrations of inflammatory markers. Moderate coffee intake is associated with a lower risk for coronary heart disease as far out as 10 years, and data suggest that an average of two cups per day protects against heart failure.

Cerebrovascular Disease and Stroke: The vascular benefits of coffee are not lost on the brain. According to a 2011 meta-analysis, consuming between one and six cups per day reportedly cut stroke risk by 17%. A 22%-25% risk reduction was seen in a large sample of Swedish women followed for an average of 10 years.

Diabetes:...Numerous studies have linked regular coffee drinking with improved glucose metabolism, insulin secretion, and a significantly reduced risk for diabetes. Most recently, findings from a long-term study published this year suggest that coffee drinkers are roughly half as likely to develop type 2 diabetes as are nonconsumers, even after accounting for smoking, high blood pressure, and family history of diabetes.

Cancer: ...Evidence suggests that moderate to heavy coffee consumption can reduce the risk for numerous cancers, including endometrial (> 4 cups/day), prostate (6 cups/day), head and neck (4 cups/day), basal cell carcinoma (> 3 cups/day), melanoma,and breast cancer (> 5 cups/day). The benefits are thought to be at least partially due to coffee's antioxidant and antimutagenic properties.

Neurodegeneration: Beyond the short-term mental boost it provides, coffee also appears to benefit longer-term cognitive well-being. A 2012 study reported that patients with mild cognitive impairment and plasma caffeine levels of > 1200 ng/mL—courtesy of approximately three to five cups of coffee per day—avoided progression to dementia over the following 2-4 years. On a related note, a study from last year reported that caffeine consumption appears to enhance memory consolidation....Caffeinated coffee has long been thought to be neuroprotective in Parkinson disease (PD)....—as well as in multiple sclerosis. 

Depression: A 2011 study suggests that a boost in coffee consumption might also benefit our mental health: Women who drank two to three cups of coffee per day had a 15% decreased risk for depression compared with those who drank less than one cup per week. A 20% decreased risk was seen in those who drank four cups or more per day. Newer work also suggests that regular coffee drinking may be protective against depression.

Liver Disease: The liver might help break down coffee, but coffee might protect the liver (in some cases). Evidence suggests that coffee consumption slows disease progression in patients with alcoholic cirrhosis and hepatitis C, and reduces the risk of developing hepatocellular carcinoma. A 2012 study reported that coffee intake is associated with a lower risk for nonalcoholic fatty liver disease (NAFLD), while work published in 2014 found that coffee protects against liver fibrosis in those with already established NAFLD.

And That's Not All…: An assortment of other research suggests that coffee intake might also relieve dry-eye syndrome by increasing tear production, reduce the risk for gout, and potentially fight infection. Coffee and hot tea consumption were found to be protective against one of the medical community's most concerning bugs, methicillin-resistant Staphylococcus aureus (MRSA). While it remains unclear whether the beverages have systemic antimicrobial activity, study participants who reported any consumption of either were approximately half as likely to have MRSA in their nasal passages.

And Finally, the Risks: As is often the case, with benefits come risks, and coffee consumption certainly has negative medical and psychiatric effects to consider. Besides the aforementioned potential increase in blood pressure, coffee can incite or worsen anxiety, insomnia, and tremor and potentially elevate glaucoma risk. Also, given the potential severity of symptoms, caffeine withdrawal syndrome is included as a diagnosis in the DSM-5.

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Trans fats are commonly used in processed foods to improve taste, texture, and shelf life. Artificial trans fats are found in partially hydrogenated oils and in other ingredients, such as refined oils, emulsifiers, flavors and colors. Even those processed foods that say zero trans fats may contain trans fats - due to a loophole in labeling laws (if it has less than .5 grams per serving, then it can be rounded down to zero - thus allowing the incorrect claim of zero trans fats). Eating a variety of processed foods, each containing a little trans fats, easily adds up to eating a significant amount daily.Trans fats in the diet have long been linked to cardiovascular disease, artherosclerosis, obesity, oxidative stress, and inflammation, but now research finds that it is linked to a poorer memory in middle-aged men under the age of 45. From Science Daily:

Dietary trans fat linked to worse memory

Higher consumption of dietary trans fatty acids (dTFA), commonly used in processed foods to improve taste, texture and durability, has been linked to worsened memory function in men 45 years old and younger, according to a study.

Researchers evaluated data from 1,018 men and women who were asked to complete a dietary survey and memory test involving word recall. On average, men aged 45 and younger recalled 86 words; however, for each additional gram of trans fats consumed daily, performance dropped by 0.76 words. This translates to an expected 12 fewer words recalled by young men with dTFA intake levels matching the highest observed in the study, compared to otherwise similar men consuming no trans fats.

After adjusting for age, exercise, education, ethnicity and mood, the link between higher dTFA and poorer memory was maintained in men 45 and younger.The study focused predominantly on men because of a small number of women in this age group. However, including women in the analysis did not change the finding, said Golomb. An association of dTFA to word memory was not observed in older populations. Golomb said this is likely due to dietary effects showing more clearly in younger adults. Insults and injuries to the brain accrue with age and add variability to memory scores that can swamp ability to detect diet effects.

Trans fatty acids have been linked to negative effects on lipid profiles, metabolic function, insulin resistance, inflammation and cardiac and general health. In 2013, the United States Food and Drug Administration issued a preliminary determination that trans fats were no longer generally recognized as safe. According to the Centers for Disease Control, reducing dTFA consumption could prevent 10,000 to 20,000 heart attacks and 3,000 to 7,000 coronary heart disease deaths per year in the U.S.

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Another study finds health benefits to eating a Mediterranean based diet (here combined with the DASH diet) - the MIND diet. The researchers found that the older adults who followed the diet best were about 7.5 years younger cognitively than those who followed it least, thus suggesting that it may slow the cognitive decline of aging. Earlier research had suggested that it may reduce a person's risk in developing Alzheimer's disease. Foods to eat: fruits, vegetables, berries, whole grains, legumes (beans), nuts, fish, a little wine, and some chicken. Foods to limit on this diet: butter, red meat, margarine, sweets and pastries, whole fat cheese, and fried or fast food. From Medical Xpress:

Eating away at cognitive decline: MIND diet may slow brain from aging by 7.5 years

While cognitive abilities naturally diminish as part of the normal aging process, it may be possible to take a bite out of this expected decline. Eating a group of specific foods known as the MIND diet may slow cognitive decline among aging adults, even when the person is not at risk of developing Alzheimer's disease, according to researchers at Rush University Medical Center. This finding is in addition to a previous study by the research team that found that the MIND diet may reduce a person's risk in developing Alzheimer's disease.

The recent study shows that older adults who followed the MIND diet more rigorously showed an equivalent of being 7.5 years younger cognitively than those who followed the diet least. The results of the study recently were published online in the journal Alzheimer's & Dementia: The Journal of the Alzheimer's Association.

The National Institute of Aging funded study evaluated cognitive change over a period of 4.7 years among 960 older adults who were free of dementia on enrollment. Averaging 81.4 years in age....residents of more than 40 retirement communities and senior public housing units in the Chicago area. .... Martha Clare Morris, ScD, a nutritional epidemiologist, and colleagues developed the diet, whose full name is the Mediterranean-DASH Diet Intervention for Neurodegenerative Delay. As the name suggests, the MIND diet is a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets. Both diets have been found to reduce the risk of cardiovascular conditions, like hypertension, heart attack and stroke.

"Everyone experiences decline with aging; and Alzheimer's disease is now the sixth leading cause of death in the U.S., which accounts for 60 to 80 percent of dementia cases. Therefore, prevention of cognitive decline, the defining feature of dementia, is now more important than ever," Morris says.

The MIND diet has 15 dietary components, including 10 "brain-healthy food groups" and five unhealthy groups - red meat, butter and stick margarine, cheese, pastries and sweets, and fried or fast food. To adhere to and benefit from the MIND diet, a person would need to eat at least three servings of whole grains, a green leafy vegetable and one other vegetable every day—along with a glass of wine—snack most days on nuts, have beans every other day or so, eat poultry and berries at least twice a week and fish at least once a week. In addition, the study found that to have a real shot at avoiding the devastating effects of cognitive decline, he or she must limit intake of the designated unhealthy foods, especially butter (less than 1 tablespoon a day), sweets and pastries, whole fat cheese, and fried or fast food (less than a serving a week for any of the three).

Berries are the only fruit specifically to be included in the MIND diet. "Blueberries are one of the more potent foods in terms of protecting the brain," Morris says, and strawberries also have performed well in past studies of the effect of food on cognitive function.

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An observational study of older adults found that the Mediterranean diet may help preserve the connections between neurons in the brain, by preserving the microstructure in the white matter of the brain. This appeared to have a strong cognitive benefit - equal up to 10 years of delayed cognitive aging in those who adhered to the Mediterranean diet most closely. So if you haven't started already, try eating what the Mediterranean diet stresses: fruits, vegetables, whole grains, seeds, nuts, legumes, olive oil, some fish, and some wine. And cut back on highly processed foods, meat, and high fat foods. It's not one or two foods, but overall diet that is important. From Medscape:

Mediterranean Diet May Preserve Brain Structural Connectivity

The Mediterranean diet may help preserve structural connectivity in the brain in older adults, results of a French study hint. Greater adherence to the Mediterranean diet was associated with preserved microstructure in extensive areas of the white matter up to a decade later, the study team found. And this appeared to be related to strong cognitive benefit, equal to up to 10 years of delayed cognitive aging for those with the greatest adherence, they say....The study was published online July 16 in Alzheimer's & Dementia. The Mediterranean diet has been associated with a lower risk for Alzheimer's disease, but the underlying mechanisms have been unclear.

The new findings are based on 146 nondemented older adults in the Bordeaux Three-City study, a prospective cohort initiated in 1999-2000 to study vascular risk factors for dementia. Participants provided information on their diet in 2001-2002 (at a mean age of 73 years), underwent brain MRI an average of 9 years later (including diffusion tensor imaging)...On the basis of dietary assessment, 26% of participants had a low Mediterranean diet (MedDi) score of 0 to 3, indicating poor adherence to the diet; 47% had medium scores (4 or 5); and 27% had higher scores (6 to 8) representing the best adherence to the diet.

In adjusted analysis, there was no significant association between the MedDi score and grey matter or white matter volume. However, there was a strong association between the MedDi and diffusion tensor imaging patterns, suggesting that higher MeDi adherence was associated with a "general pattern of preserved WM [white matter] microstructure in multiple bundles," the researchers say. And preserved white matter microstructure with higher adherence to the MedDi "appeared to delay cognitive aging by up to 10 years."

"Our results suggest that the Mediterranean diet helps preserve the connections between neurons, which appear to be damaged with aging, vascular brain diseases and neurodegenerative diseases such as Alzheimer's dementia," Dr Samieri told Medscape Medical News. "In addition, the regions which appeared preserved with greater adherence to the Mediterranean diet were extended and were not specific to a particular disease, suggesting that the Mediterranean diet may have the potential to prevent not only stroke (as previously demonstrated with the PREDIMED [Prevención con Dieta Mediterránea] trial) but also multiple age-related brain pathologies," she added.

The added finding that none of the individual components of the Mediterranean diet was strongly associated with imaging results "supports our hypothesis that overall diet quality may be more important to preserve brain structure than any single food," they write.