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Eight nutrients to protect the aging brain

 

Brain health is the second most important component in maintaining a healthy lifestyle according to a 2014 AARP study. As people age they can experience a range of cognitive issues from decreased critical thinking to dementia and Alzheimer's disease. In the March issue of Food Technology published by the Institute of Food Technologists (IFT), contributing editor Linda Milo Ohr writes about eight nutrients that may help keep your brain in good shape. 1. Cocoa Flavanols: Cocoa flavanols have been linked to improved circulation and heart health, and preliminary research shows a possible connection to memory improvement as well. A study showed cocoa flavanols may improve the function of a specific part of the brain called the dentate gyrus, which is associated with age-related memory (Brickman, 2014). 2. Omega-3 Fatty Acids: Omega-3 fatty acids have long been shown to contribute to good heart health are now playing a role in cognitive health as well. A study on mice found that omega-3 polyunsaturated fatty acid supplementation appeared to result in better object recognition memory, spatial and localizatory memory (memories that can be consciously recalled such as facts and knowledge), and adverse response retention (Cutuli, 2014). Foods rich in omega-3s include salmon, flaxseed oil, and chia seeds. 3. Phosphatidylserine and Phosphatidic Acid: Two pilot studies showed that a combination of phosphatidylserine and phosphatidic acid can help benefit memory, mood, and cognitive function in the elderly (Lonza, 2014). 4. Walnuts: A diet supplemented with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of Alzheimer's disease in mice (Muthaiyah, 2014). 5. Citicoline: Citicoline is a natural substance found in the body's cells and helps in the development of brain tissue, which helps regulate memory and cognitive function, enhances communication between neurons, and protects neural structures from free radical damage. Clinical trials have shown citicoline supplements may help maintain normal cognitive function with aging and protect the brain from free radical damage. (Kyowa Hakko USA). 6. Choline: Choline, which is associated with liver health and women's health, also helps with the communication systems for cells within the brain and the rest of the body. Choline may also support the brain during aging and help prevent changes in brain chemistry that result in cognitive decline and failure. A major source of choline in the diet are eggs. 7. Magnesium: Magnesium supplements are often recommended for those who experienced serious concussions. Magnesium-rich foods include avocado, soy beans, bananas and dark chocolate. 8. Blueberries: Blueberries are known to have antioxidant and anti-inflammatory activity because they boast a high concentration of anthocyanins, a flavonoid that enhances the health-promoting quality of foods. Moderate blueberry consumption could offer neurocognitive benefits such as increased neural signaling in the brain centers. Story Source: The above story is based on materials provided by Institute of Food Technologists (IFT). Note: Materials may be edited for content and length.

Alcohol use: If you drink, keep it moderate

 

Alcohol use can be a slippery slope. Moderate drinking can offer some health benefits. But heavy drinking can have serious consequences. By Mayo Clinic Staff It sounds like a mixed message: Drinking alcohol may offer some health benefits, especially for your heart. On the other hand, alcohol may increase your risk of health problems and damage your heart. So which is it? When it comes to drinking alcohol, the key is doing so only in moderation. Certainly, you don't have to drink any alcohol, and if you currently don't drink, don't start drinking for the possible health benefits. In some cases, it's safest to avoid alcohol entirely — the possible benefits don't outweigh the risks. Here's a closer look at the connection between alcohol and your health. Health benefits of moderate alcohol use Moderate alcohol consumption may provide some health benefits. It may: Reduce your risk of developing and dying from heart disease Possibly reduce your risk of ischemic stroke (when the arteries to your brain become narrowed or blocked, causing severely reduced blood flow) Possibly reduce your risk of diabetes Even so, the evidence about the possible health benefits of alcohol isn't certain, and alcohol may not benefit everyone who drinks. Guidelines for moderate alcohol use If you choose to drink alcohol, do so only in moderation. For healthy adults, that means up to one drink a day for women of all ages and men older than age 65, and up to two drinks a day for men age 65 and younger. Examples of one drink include: Beer: 12 fluid ounces (355 milliliters) Wine: 5 fluid ounces (148 milliliters) Distilled spirits (80 proof): 1.5 fluid ounces (44 milliliters) Moderate alcohol use may be of most benefit if you're an older adult or if you have existing risk factors for heart disease. If you're a middle-aged or younger adult, some evidence shows that even moderate alcohol use may cause more harm than good. You can take other steps to benefit your cardiovascular health besides drinking — eating a healthy diet and exercising, for example. When to avoid alcohol use In certain situations, the risks of alcohol use may outweigh the possible health benefits. For example, use alcohol only with great care and after consulting your doctor if: You're pregnant or trying to become pregnant You've been diagnosed with alcoholism or alcohol abuse, or you have a strong family history of alcoholism You have liver or pancreatic disease You have heart failure or you've been told you have a weak heart You take prescription or over-the-counter medications that can interact with alcohol You've had a hemorrhagic stroke (when a blood vessel in your brain leaks or ruptures) Keep in mind that even moderate use isn't risk-free. For example, drinking and driving is never a good idea. The risks of heavy alcohol use Heavy drinking is defined as more than three drinks on any day or more than seven drinks a week for women and for men older than age 65, and more than four drinks on any day or more than 14 drinks a week for men age 65 and younger. Binge drinking is defined as four or more drinks within two hours for women and five or more drinks within two hours for men. While moderate alcohol use may offer some health benefits, heavy drinking — including binge drinking — has no health benefits. Excessive drinking can increase your risk of serious health problems, including: Certain cancers, including breast cancer and cancers of the mouth, pharynx, larynx and esophagus Pancreatitis Sudden death if you already have cardiovascular disease Heart muscle damage (alcoholic cardiomyopathy) leading to heart failure Stroke High blood pressure Liver disease Suicide Accidental serious injury or death Brain damage and other problems in an unborn child Alcohol withdrawal syndrome Drink alcohol only in moderation — or not at all The latest dietary guidelines make it clear that no one should begin drinking or drink more frequently on the basis of potential health benefits. So don't feel pressured to drink alcohol. But if you do drink alcohol and you're healthy, there's probably no need to stop as long as you drink responsibly and in moderation.

Video games can power up from merely fun to meaningful experiences

 

It may be game over for critics who claim that video games are nothing more than a fun diversion. A team of researchers suggests that many games can be meaningful entertainment experiences for players. In a study of people's experiences with video games, players indicated that they not only enjoyed playing games, but that they also frequently appreciated them at a deeper, more meaningful level. These findings should be encouraging to video game developers who want to invest in producing games that examine more meaningful, poignant or contemplative topics. "Video games are often stereotyped as something that is just fun and entertaining, but not something that is deeply appreciated," said Mary Beth Oliver, Distinguished Professor in Media Studies and co-director of Media Effects Research Laboratory, Penn State. "Video games do not seem to have the same critical acclaim as, for example, books and plays or even music." Participants in the study suggested that story details in the game were critical to feelings of appreciation. They also indicated that more meaningful games were associated with heightened feelings of insight or enrichment. "That insight could be anything from an emotion or virtue -- like courage -- to an insight on human spirituality," said Oliver. The researchers, who report their findings in the current issue of Psychology of Popular Media Culture, said games may hold promise of providing players with enriching or gratifying experiences. "It's certainly true that there are some games that are silly or shallow, but that's the case for almost all forms of entertainment," said Oliver. "Our research suggests that contrary to stereotypes, games have the potential to be as meaningful to players as other, more esteemed forms of entertainment such as literature or cinema." Games may also provide players the opportunity to experience valuable situations and emotions that other forms of entertainment may not do as frequently, Oliver added. "Whereas viewers and readers typically watch characters make decisions in movies and books, many video games allow the player to actually make those choices, resulting in feelings such as guilt or pride," she added. Creating games with more interactive and more meaningful story lines is a challenge for developers, but could be worth the investment, the researchers indicate. The increased focus on narrative and emotions is a natural evolution in video games, said Nick Bowman, assistant professor of communication studies and a research associate, West Virginia University, who worked with Oliver. "The earliest video games really had very little in common with other forms of narrative entertainment," said Bowman. "Games have grown from simple point-and-click twitch games to incredibly engrossing emotional experiences and games now have the potential to give us the same sorts of feelings that great novels and music do." For example, Bowman said at one point in the game Spec Ops, the player is faced with the moral decision to use chemical weapons on an enemy. One consequence of choosing to do so is that innocent refugees are victims of the attack. The player is forced to witness the results of his or her actions, triggering a mix of emotions. "Such an experience gives players a space to challenge how they see the world, just as movies like Schindler's List or novels like Animal Farm, did for past audiences," said Bowman. "Video games have grown up." In the study, 512 video game players were assigned to one of two random groups and asked to recall games that were particularly fun or particularly meaningful. They then rated their perceptions about the game. While participants reported that they found both types were fun to play, they said they had more appreciation for the more meaningful games they played.

Teachers more likely to label black students as troublemakers

 

Teachers are likely to interpret students' misbehavior differently depending on the student's race, according to new research findings published in Psychological Science, a journal of the Association for Psychological Science. Racial differences in school discipline are widely known, and black students across the United States are more than three times as likely as their white peers to be suspended or expelled, according to Stanford researchers. Yet the psychological processes that contribute to those differences have not been clear -- until now. "The fact that black children are disproportionately disciplined in school is beyond dispute," said Stanford psychology Professor Jennifer Eberhardt in an interview. "What is less clear is why." Eberhardt and Stanford psychology graduate student Jason Okonofua examined the psychological processes involved when teachers discipline black students more harshly than white students. In the studies, real-world primary and secondary school teachers were presented with school records describing two instances of misbehavior by a student. In one study, after reading about each infraction, the teachers were asked about their perception of its severity, about how irritated they would feel by the student's misbehavior, about how severely the student should be punished, and about whether they viewed the student as a troublemaker. A second study followed the same protocol and asked teachers whether they thought the misbehavior was part of a pattern and whether they could imagine themselves suspending the student in the future. The researchers randomly assigned names to the files, suggesting in some cases that the student was black (with a name such as DeShawn or Darnell) and in other cases that the student was white (with a name such as Greg or Jake). Across both studies, the researchers found that racial stereotypes shaped teachers' responses not after the first infraction but rather after the second. Teachers felt more troubled by a second infraction they believed was committed by a black student rather than by a white student. In fact, the stereotype of black students as "troublemakers" led teachers to want to discipline black students more harshly than white students after two infractions, Eberhardt and Okonofua said. They were more likely to see the misbehavior as part of a pattern, and to imagine themselves suspending that student in the future. "We see that stereotypes not only can be used to allow people to interpret a specific behavior in isolation, but also stereotypes can heighten our sensitivity to behavioral patterns across time. This pattern sensitivity is especially relevant in the schooling context," Eberhardt said. These results have implications beyond the school setting as well. As Okonofua said, "Most social relationships entail repeated encounters. Interactions between police officers and civilians, between employers and employees, between prison guards and prisoners all may be subject to the sort of stereotype escalation effect we have identified in our research." Both Okonofua and Eberhardt suggested that useful interventions with teachers would help them to view student behavior as malleable rather than as a reflection of a fixed disposition, such as that of troublemaker. While racial disparities can be lessened by psychological interventions that help improve black students' behaviors in class, it is also important to understand how that behavior is interpreted by teachers and school authorities, Okonofua said.

New potential cause for Alzheimer's: Arginine deprivation caused by overconsumption by immune cells

 

A new Duke University study in mice suggests that in Alzheimer's disease, certain immune cells that normally protect the brain begin to abnormally consume an important nutrient: arginine. Blocking this process with a small-molecule drug prevented the characteristic brain plaques and memory loss in a mouse model of the disease.

Published April 15 in the Journal of Neuroscience, the new research not only points to a new potential cause of Alzheimer's but also may eventually lead to a new treatment strategy.

"If indeed arginine consumption is so important to the disease process, maybe we could block it and reverse the disease," said senior author Carol Colton, professor of neurology at the Duke University School of Medicine, and a member of the Duke Institute for Brain Sciences.

The brains of people with Alzheimer's disease show two hallmarks -- 'plaques' and 'tangles' -- that researchers have puzzled over for some time. Plaques are the build up of sticky proteins called beta amyloid, and tangles are twisted strands of a protein called tau.

In the study, the scientists used a type of mouse, called CVN-AD, that they had created several years ago by swapping out a handful of important genes to make the animal's immune system more similar to a human's.

Compared with other mice used in Alzheimer's research, the CVN-AD mouse has it all: plaques and tangles, behavior changes, and neuron loss.

In addition, the gradual onset of these symptoms in the CVN-AD mouse gave researchers a chance to study its brain over time and to focus on how the disease begins, said the study's first author Matthew Kan, an MD/PhD student in Colton's lab.

Looking for immune abnormalities throughout the lifespan of the mice, the group found that most immune system components stayed the same in number, but a type of brain-resident immune cells called microglia that are known first responders to infection begin to divide and change early in the disease.

The microglia express a molecule, CD11c, on their surface. Isolating these cells and analyzing their patterns of gene activity, the scientists found heightened expression of genes associated with suppression of the immune system. They also found dampened expression of genes that work to ramp up the immune system.

"It's surprising, because [suppression of the immune system is] not what the field has been thinking is happening in AD," Kan said. Instead, scientists have previously assumed that the brain releases molecules involved in ramping up the immune system, that supposedly damage the brain.

The group did find CD11c microglia and arginase, an enzyme that breaks down arginine, are highly expressed in regions of the brain involved in memory, in the same regions where neurons had died.

Blocking arginase using the small drug difluoromethylornithine (DFMO) before the start of symptoms in the mice, the scientists saw fewer CD11c microglia and plaques develop in their brains. These mice performed better on memory tests.

"All of this suggests to us that if you can block this local process of amino acid deprivation, then you can protect -- the mouse, at least -- from Alzheimer's disease," Kan said.

DFMO is being investigated in human clinical trials to treat some types of cancer, but it hasn't been tested as a potential therapy for Alzheimer's. In the new study, Colton's group administered it before the onset of symptoms; now they are investigating whether DFMO can treat features of Alzheimer's after they appear.

Does the study suggest that people should eat more arginine or take dietary supplements? The answer is 'no,' Colton said, partly because a dense mesh of cells and blood vessels called the blood-brain barrier determines how much arginine will enter the brain. Eating more arginine may not help more get into the sites of the brain that need it. Besides, if the scientists' theory is correct, then the enzyme arginase, unless it's blocked, would still break down the arginine.

"We see this study opening the doors to thinking about Alzheimer's in a completely different way, to break the stalemate of ideas in AD," Colton said. "The field has been driven by amyloid for the past 15, 20 years and we have to look at other things because we still do not understand the mechanism of disease or how to develop effective therapeutics."