Monday, January 11, 2016

Best Diet for Your Brain

Brain Foods You Should Be Eating

 

Chances are, you purposely ate something today that you know is heart-healthy, but did you think about consuming some foods that are good for your brain? Probably not. Only relatively recently have researchers begun to study the link between diet and cognitive function, and the findings are promising.
“You can’t control your genes, which are mostly responsible for any decline in brain function as we age, but with diet, there’s the potential to do something,” says Lon S. Schneider, M.D., a professor of psychiatry, neurology, and gerontology at the University of Southern California.
But it takes more than eating familiar brain foods such as fish or blueberries once in a while. “It’s what we eat as a whole,” says Martha Clare Morris, Sc.D., director of nutrition and nutritional epidemiology at the Rush University Medical Center. Research by Morris and her colleagues shows that following a diet that includes the right brain foods in the right combination can take years off your brain. 

Introducing the MIND diet

The MIND diet is a hybrid of the heart-healthy Mediterranean and the blood-pressure-lowering DASH diets. (MIND stands for Mediterranean-DASH Intervention for Neurodegenerative Delay.) It limits red meat, butter and stick margarine, pastries and sweets, fried and fast food, and cheese. But a few foods play starring roles.
The Rush team created the plan after reviewing the evidence from human and animal studies on diet and brain health, and singled out foods that appeared to have brain-protecting effects. Then they studied the diets of almost 1,000 elderly adults, who were followed for an average of 4½ years. People whose diets were most strongly in line with the MIND diet had brains that functioned as if they were 7½ years younger than those whose diets least resembled this eating style. A follow-up study showed that they also cut their risk of developing Alzheimer’s disease in half. People who followed the plan only some of the time still had a 35 percent lower risk. Working these brain foods into your diet can help keep your mind sharp and your entire body healthy.  

How do you keep your memory sharp?

Share your tips by leaving a comment below.

1. Vegetables/Leafy Greens

It’s not yet clear how greens improve brain health, but it may be because of their high levels of vitamin K, folate (a B vitamin), and the antioxidants beta carotene and lutein. People who had one to two servings of greens per day, such as collards, kale, and spinach, for about five years had the cognitive abilities of someone 11 years younger, according to another study from Rush University. All types of lettuce and greens count, but darker greens have more nutrients.
Eat at least one cup raw or ½ cup cooked greens and ½ cup of other cooked vegetables per day.
How to use them: 
Mix a handful of baby spinach or kale into an almost-ready pasta dish or soup, the heat will wilt the greens.

2. Nuts

The brains of older women who ate five servings of nuts per week functioned similarly to those of women 2 years younger, according to a study in the Journal of Nutrition, Health and Aging. A small study found that older men and women who ate just one Brazil nut daily for six months experienced increases in blood selenium levels as well as better verbal abilities and spatial skills. Brazil nuts contain selenium, a mineral that helps boost the activity of antioxidants that may protect the brain from damage. One nut supplies all of the selenium you need in a day.
Eat at least five 1-ounce servings per week
How to use them: Toss a handful of the nuts (or a chopped Brazil nut) on your salad instead of croutons for a nutrient-packed crunch. Stash 100-calorie snack packs in your bag or desk for the midday munchies.

3. Berries

According to the MIND research, berries are the only fruit that benefit the brain. Women ages 70 and older who ate blueberries at least once per week or strawberries twice per week or more had a brain age as much as 2½ years younger than those who ate the berries less than once per month, according to a Harvard study that followed more than 16,000 women for almost 20 years. One animal study suggests that the antioxidants in berries can help activate the brain’s “housekeeper” mechanism, which cleans out parts of cells that become damaged. Frozen berries are just as nutritious as fresh and can cost half as much.
Eat at least one cup twice per week
How to use them: Toss frozen berries into a smoothie or heat them in a saucepan and use as a topping for oatmeal.

4. Beans

Eating black beans, kidney beans, lentils, white beans, and others provides a hearty dose of folate, a B vitamin that may play a role in preventing dementia later in life, according to a study in the Journal of the Academy of Nutrition and Dietetics. Canned beans are fine; just rinse them before using to remove some of the sodium.
Eat at least ½ cup cooked, four times per week.
How to use them: Cook white beans with rosemary and garlic, then drizzle them with olive oil for a rich but healthy side dish. Or snack on hummus or try one of the new bean-based pastas on the market.

5. Fish/Poultry

Both are much lower in saturated fat than red meat. And the omega 3 fats in fish may improve learning and memory by increasing the brain’s ability to send and receive messages. Older adults without dementia who ate 3 to 5 ounces of fish weekly for the past year experienced less brain shrinkage, a common occurrence with Alzheimer’s disease, compared with people who hardly ever ate fish.
“In general, the more fish, the better,” says Yian Gu, Ph.D., an assistant professor of neuropsychology at Columbia University. She cautions, however, that people should weigh the possible benefits of fish consumption against the risks of mercury and other toxins that fish may contain. Low-mercury options include haddock, sardines, tilapia, and wild salmon.
Eat at least 3 ounces of fish and 6 ounces of poultry per week (not fried).
How to use them: Replace tuna with canned salmon (it’s often wild) for salads or make salmon burgers. Roll chopped chicken breast into a whole-wheat wrap with ¼ cup avocado, ½ cup shredded lettuce, and 2 tablespoons of salsa.

6. Olive Oil

The phenolic compounds in extra-virgin olive oil may help prevent toxic protein deposits that can lead to the progression of Alzheimer’s disease, according to research from the University of Florence. Olive oil may also help reduce inflammation and improve blood-vessel function, two factors that can benefit the brain, according to a review of 30 studies published in the journal Nutrients.
Recommended intake: Daily
How to use it: Cook with it and use it on salads and vegetables.

7. Whole Grains

Whole grains, like bulgur and quinoa, were associated with higher levels of brain function in a study that tracked the diet of men and women age 65 and older.
Eat at least ½ cup cooked grains or a slice of whole-grain bread three times per day.
How to use them: Start the morning with a bowl of oatmeal. For lunch or dinner, toss wheat berries with chopped vegetables, beans, olive oil, and vinegar for an alternative to pasta salad.

8. Wine

Moderate wine drinking is linked to better brain health, but beware of a cup that runneth over. Adults who averaged more than 12 grams of alcohol per day (about the amount in 4 ounces of wine) had an increased risk of developing dementia, according to a study from the University of South Florida. If you’re at a high risk for cancer, ask your doctor how much you should drink.
Recommended intake: One glass per day.

A Day on the MIND Diet

A day’s worth of meals focused on brain foods looks a lot like a Mediterranean heart-health plan. There are lots of veggies, nuts, whole grains, and olive oil; some beans, fish, and poultry; and a daily glass of wine. What you won’t see much of is red meat, sweets, or fried and fast foods. Remember: Eating this way even some of the time has been linked to brain benefits.
Breakfast: 1 cup of oatmeal prepared with water, topped with ½ cup blueberries and 2 tablespoons chopped walnuts. Coffee with milk, no sugar.
Snack: 1 apple and 1 ounce of almonds.
Lunch: A salad of 3 cups of baby spinach with ¼ cup each of chopped cucumber, tomato, and bell pepper; ¼ cup quinoa; ⅓ cup chickpeas; 3 ounces sliced chicken; 2 tablespoons extra-virgin olive oil; and 1 tablespoon vinegar.
Dinner: Grilled tilapia with olive oil and lemon, ½ cup of farro, 1 cup of string beans sautéed in garlic and olive oil, one glass of pinot noir.
Dessert: 1 cup sliced strawberries drizzled with balsamic vinegar.

Dieting has increased in recent decades, but interestingly, so has obesity. In the midst of so many people struggling to lose weight and keep it off, a new study suggests that the problem may lie in the brain. Results show that the ability to self-regulate body weight could be down to each individual's brain structure.
The study was published in the journal Cognitive Neuroscience.
Obesity is a problem worldwide but particularly in the United States. Over one third of adults in the U.S. are obese, and the 2008 annual medical costs for people who were obese were $1,429 higher than for those who were of a normal weight.
Additionally, obesity increases risks for heart disease, stroke, type 2 diabetes, and certain types of cancer - which are some of the leading causes of preventable death.
According to the researchers of the latest study, chronic dieters are known to show extreme reactions to food cues in both the executive control and reward areas of the brain.
To further investigate, the team carried out their research on a group of 36 chronic female dieters who had a mean body fat percentage of 29.6 and a mean body mass index (BMI) of 23.9.
According to the Centers for Disease Control and Prevention (CDC), BMI can be an indicator of body fatness. If BMI is less than 18.5, a person is considered underweight. BMI between 18.5-25 is considered normal, whereas 25-30 is overweight and 30 or higher is considered obese.
The researchers asked the study participants to make simple judgments on images to avert their attention from the real task at hand, which was a food cue reactivity task. This was designed to pinpoint the executive control and reward areas in the brain through functional magnetic resonance imaging (fMRI).

'Structural integrity in brain coincides with individual body fat differences'

Once the researchers had identified the executive and control reward areas, they used diffusion tensor imaging (DTI) to establish the integrity of the white matter track that connects these areas.
Based on the fMRI results, the team found that the participants showed greater reactivity to food images than control images.
Furthermore, the DTI results showed that participants with lower body fat percentages had greater white matter integrity between the executive control and reward areas of the brain.
The researchers note that it is unclear whether these differences in white matter integrity resulted from repeat dieting.
However, they add that although "a previous study found that repeatedly practicing a task can lead to increased [measures of white matter integrity] in particular fiber tracts, it is also possible that failures in dieting lead to obesity and obesity-related factors."
The team says the findings support their hypothesis that structural integrity in the brain coincides with individual body fat differences. They say it is also indicative of dieting success and add:

"Individuals with reduced integrity may have difficulty in overriding rewarding temptations, leading to a greater chance of becoming obese than those with higher structural integrity."
It is important to note that the study only included female dieters, so whether the results also apply to men is still unknown. The researchers say further study is needed to determine whether these same effects apply to male dieters.
Read about how stronger muscles lead to a stronger brain.
 Think about it. Your brain is always “on.” It takes care of your thoughts and movements, your breathing and heartbeat, your senses — it works hard 24/7, even while you’re asleep. This means your brain requires a constant supply of fuel. That “fuel” comes from the foods you eat — and what’s in that fuel makes all the difference. Put simply, what you eat directly affects the structure and function of your brain and, ultimately, your mood.
Like an expensive car, your brain functions best when it gets only premium fuel. Eating high-quality foods that contain lots of vitamins, minerals, and antioxidants nourishes the brain and protects it from oxidative stress — the “waste” (free radicals) produced when the body uses oxygen, which can damage cells.
Unfortunately, just like an expensive car, your brain can be damaged if you ingest anything other than premium fuel. If substances from “low-premium” fuel (such as what you get from processed or refined foods) get to the brain, it has little ability to get rid of them. Diets high in refined sugars, for example, are harmful to the brain. In addition to worsening your body’s regulation of insulin, they also promote inflammation and oxidative stress. Multiple studies have found a correlation between a diet high in refined sugars and impaired brain function — and even a worsening of symptoms of mood disorders, such as depression.
It makes sense. If your brain is deprived of good-quality nutrition, or if free radicals or damaging inflammatory cells are circulating within the brain’s enclosed space, further contributing to brain tissue injury, consequences are to be expected. What’s interesting is that for many years, the medical field did not fully acknowledge the connection between mood and food.
Today, fortunately, the burgeoning field of nutritional psychiatry is finding there are many consequences and correlations between not only what you eat, how you feel, and how you ultimately behave, but also the kinds of bacteria that live in your gut.

How the foods you eat affect how you feel

Serotonin is a neurotransmitter that helps regulate sleep and appetite, mediate moods, and inhibit pain. Since about 95% of your serotonin is produced in your gastrointestinal tract, and your gastrointestinal tract is lined with a hundred million nerve cells, or neurons, it makes sense that the inner workings of your digestive system don’t just help you digest food, but also guide your emotions. What’s more, the function of these neurons — and the production of neurotransmitters like serotonin — is highly influenced by the billions of “good” bacteria that make up your intestinal microbiome. These bacteria play an essential role in your health. They protect the lining of your intestines and ensure they provide a strong barrier against toxins and “bad” bacteria; they limit inflammation; they improve how well you absorb nutrients from your food; and they activate neural pathways that travel directly between the gut and the brain.
Studies have shown that when people take probiotics (supplements containing the good bacteria), their anxiety levels, perception of stress, and mental outlook improve, compared with people who did not take probiotics. Other studies have compared “traditional” diets, like the Mediterranean diet and the traditional Japanese diet, to a typical “Western” diet and have shown that the risk of depression is 25% to 35% lower in those who eat a traditional diet. Scientists account for this difference because these traditional diets tend to be high in vegetables, fruits, unprocessed grains, and fish and seafood, and to contain only modest amounts of lean meats and dairy. They are also void of processed and refined foods and sugars, which are staples of the “Western” dietary pattern. In addition, many of these unprocessed foods are fermented, and therefore act as natural probiotics. Fermentation uses bacteria and yeast to convert sugar in food to carbon dioxide, alcohol, and lactic acid. It is used to protect food from spoiling and can add a pleasant taste and texture.
This may sound implausible to you, but the notion that good bacteria not only influence what your gut digests and absorbs, but that they also affect the degree of inflammation throughout your body, as well as your mood and energy level, is gaining traction among researchers. The results so far have been quite amazing.

What does this mean for you?

Start paying attention to how eating different foods makes you feel — not just in the moment, but the next day. Try eating a “clean” diet for two to three weeks — that means cutting out all processed foods and sugar. Add fermented foods like kimchi, miso, sauerkraut, pickles, or kombucha. You also might want to try going dairy-free — and some people even feel that they feel better when their diets are grain-free. See how you feel. Then slowly introduce foods back into your diet, one by one, and see how you feel.
When my patients “go clean,” they cannot believe how much better they feel both physically and emotionally, and how much worse they then feel when they reintroduce the foods that are known to enhance inflammation. Give it a try!

I recently stumbled onto a book that opened my eyes in many ways to the misinformation plaguing Americans regarding healthy eating, particularly where it concerns brain health. The book, Grain Brain, by Dr. David Perlmutter, is mind-blowing—no pun intended—and disruptive to some long-standing beliefs about what our bodies require for optimal health.
"The brain thrives on a fat-rich, low-carbohydrate diet, which unfortunately is relatively uncommon in human populations today," he says. Carbohydrates typically thought of as healthy, even brown rice, 100% whole grain bread, or quinoa—mainstays of many of the most health-conscious kitchens—cause disorders like dementia, ADHD, chronic headaches, and Alzheimer’s, over a lifetime of consumption. By removing these carbohydrates from the diet—harbingers of inflammation, the true source of problems that plague our brains and hearts—and increasing the amount of fat and cholesterol we consume, we can not only protect our most valuable organ, but also potentially, undo years of damage. Cholesterol, for example, long vilified by the media and medical community, actually promotes neurogenesis (the birth of new brain cells) and communication between neurons, to the degree that studies have shown that higher levels of serum cholesterol correlates to more robust cognitive prowess.
The book is also not without serious consideration for cardiovascular system, citing study after study to reaffirm that it’s not fat and cholesterol, but carbohydrates and certain fats—and not the fats that you would think—that are the true enemies of heart and vascular health. Guidelines to eating for above-average health and longevity are not without nuance, but Grain Brain lays out an easy-to-understand roadmap packed with the latest science in a colloquial writing style, never once doubting the ability of its audience to keep up.
As the only doctor in the country who is both a board-certified neurologist and Fellow of The American Board of Nutrition, he deftly covers a topic rarely discussed: How what we eat affects the health of our brain. And considering that deaths from Alzheimer's increased 68 percent between 2000 and 2010, the timing of Grain Brain couldn’t be better.
After reading it, I couldn't wait to sit down with him for a Q&A. (My questions are in bold.)
You’ve stated that carbs of any kind, from natural sugars in fruit to the complex carbs in quinoa and a whole wheat bagel, are detrimental to the brain, to the point that the most serious degenerative brain disorders, including Alzheimer’s disease, are now being referred to as “Type 3 diabetes”. What’s the science behind this?
Carbohydrate consumption leads to blood sugar elevation obviously in the short term, but also, in the long term as well. Persistently challenging the pancreas to secrete insulin to deal with dietary carbohydrate ultimately leads to insulin resistance, a condition directly associated with increased risk for dementia. What’s worse, insulin resistance is the forerunner of type 2 diabetes, a condition associated with a doubling of Alzheimer’s risk. In a recent report in the Journal of Alzheimer’s Disease., Mayo Clinic researchers showed that individuals favoring carbohydrates in their diets had a remarkable 89% increased risk for developing dementia as contrasted to those whose diets contained the most fat. Having the highest levels of fat consumption was actually found to be associated with an incredible 44% reduction in risk for developing dementia.
So-called “complex carbs” may actually represent a more significant threat to health than simple sugar in that they may not only raise blood sugar, but keep it elevated for a more prolonged period of time. Foods can be evaluated by their glycemic index which measures not only how high blood sugar will be elevated by the consumption of a particular food, but also takes into account how long it will have this effect. So the higher the glycemic index, the more damaging are the effects of elevated blood sugar. Whole grain bread for example has a dramatically higher glycemic index when compared to pure table sugar.
Ultimately, continued challenges of our bodies with high glycemic index foods leads to elevation of fasting blood sugars. This is of paramount importance as recently published in New England Journal of Medicine. In this report, researchers found that a fasting blood sugar even in the range that most doctors would consider to be normal, levels far below what would qualify for the diagnosis, are powerfully associated with developing dementia.
In your book you challenge some of the most commonly accepted dogmas regarding nutrition, namely that both saturated fat and cholesterol are not only benign, but imperative to brain health. If someone is suffering from brain dysfunction, would you actually recommend that they consume more red meat, whole eggs, coconut oil as treatment?
Two forms of fat that are vitally important for brain health are cholesterol and saturated fat. In the Mayo Clinic study mentioned above, it was found that those individuals consuming the most saturated fat experienced a 36% reduction in risk for developing dementia. And this comes on the heels of data now indicating that saturated fat consumption has absolutely no relevance in the area of cardiovascular risk as recently described by Dr. Glen Lawrence in the journal, Advances in Nutrition.
Saturated fat is a fundamental building block for brain cells. It’s certainly interesting to consider that one of the richest sources of saturated fat in nature is human breast milk.
Similarly, cholesterol is vital for a well functioning brain. Cholesterol functions as a brain protective antioxidant. It is the raw material from which our bodies make vitamin D, a fundamental player in preserving brain function. In addition, cholesterol is the precursor for the sex hormones estrogen, progesterone and testosterone – all of which contribute to healthy brain function. While the brain constitutes about 2-3% of our total body weight, an impressive 25% of the body’s cholesterol is found in the brain. So when the FDA last year began requiring consumer warnings on certain cholesterol lowering medications related to memory decline and other cognitive issues, it wasn’t surprising. Indeed, it has now been shown that in the elderly, those folks whose cholesterol levels are the highest may have as much as a 70% risk reduction for dementia.
So yes, I am absolutely an advocate for grass-fed beef, pasture raised eggs, and coconut oil is on the top of my list. Getting these life sustaining, brain nurturing fats back on the plate while substantially reducing carbohydrates paves the way to brain preservation, enhancement of function and reducing the risk for Alzheimer’s disease – a disease for which there is no treatment whatsoever.

I’ve read many reports about statins, drugs commonly prescribed to lower cholesterol, like Lipitor—netting pharmaceutical companies $35 billion in sales in 2010—producing dementia-like effects in patients, which seems like an awful side effect. Why has the public not made a bigger deal of this? In general, the public knowledge base and thus decision-making behaviors are far more influenced by advertisement than with current science. The widespread demonization of cholesterol has been incredibly monetized as you well point out. My mission is to offer up the other side of this debate to the public forum so caveat emptor can more appropriately apply.
You reference many studies that challenge conventional wisdom about heart health, most interestingly that people with high cholesterol and low cholesterol tend to have just as many heart attacks and die just as frequently. Should a diagnosis of “high cholesterol” from ones internist be alarming? Are there any cases in which it should be controlled by medicine or diet?
Over the past decade we have witnessed a changing landscape in terms of refinement of the cholesterol markers as they relate to cardiovascular risk. Whereas cholesterol itself was first targeted, emphasis soon moved to LDL as it was given the name “bad cholesterol,” despite the fact that LDL’s role is to deliver life sustaining cholesterol to every one of our body’s cells. I’ll say parenthetically that whatever marketing team attached the “bad “ surname to LDL must have been well rewarded! We then saw emphasis move to the importance of so-called “particle size” as being an important marker of cardiovascular risk – and rightfully so, size really does matter.
Now the focus of attention has gone back to LDL in recognizing that it truly represents a potent risk factor when it has become oxidized. Oxidation represents the damage that can occur to proteins by the action of chemicals called free radicals. So, measurement of oxidized LDL is now showing up on comprehensive heart disease blood panels, and with good reason. The empowering science here is that LDL gets oxidized when it is bound to sugar, a process called glycation. And this process is directly related to fasting blood sugar and therefore relates to a person’s choice to consume carbohydrates – or not. In evaluating cholesterol in and of itself, I do not define any upper limit in terms of cardiac liability. 
A recent report correlated higher intake of omega 3 fish oils—which we know from Grain Brain to be very healthy and protective to the brain—with a greater incidence of acquiring prostate cancer. I was always under the assumption that the more omega 3's you could consume, the better (while minimizing omega 6's, their pro-inflammatory cousin). What's your take on the study? 
The study had actually nothing to do with taking fish oils or any supplement for that matter. And yet spinmeisters would have you believe that this report dealt with people taking supplements compared to those who did not. What the study showed was that those men whose one time measurement of the omega-3 DHA was higher than others were found to have a miniscule increased risk for developing prostate cancer. The explanation that the public did not get was that because most men get their DHA from fish consumption as opposed to supplementation, and that the vast majority of fish consumed is farm raised, eating farm raised fish poses a risk for developing prostate cancer. And that is certainly no surprise.
My grandmother is 96 years old and has never even heard of gluten. Because of the seemingly overnight hysteria surrounding this grain protein, some have written it off as a fad. How do you refute this? 
In writing Grain Brain, I reviewed more than 250 peer-reviewed references, many of which specifically address this issue and are discussed in great detail. Gluten free isn’t new or a fad. It’s the diet that humans have consumed for more than 99.9% of our existence on this planet. I would direct your readers to recent publication by my friend and colleague Dr. Alessio Fasano from Harvard. I welcome the hysteria as it is directing attention to an absolutely fundamental issue in our modern nutrition.
If someone is not suffering from celiac disease, and generally feels okay after consuming bread—even 100% whole grain bread—how do you convince them that wheat is as detrimental as you claim in the book?
I must and should defer to the most well respected peer-reviewed literature that now indicates that gluten consumption leads to the amplification of a specific protein called zonulin which increases permeability of both the gut and blood brain barrier as described by Dr. Fasano in the above reference. Gut permeability activates inflammation and inflammation is a cornerstone of some of the most pernicious brain disorders including Alzheimer’s disease, multiple sclerosis, and Parkinson’s disease. What is so compelling in a very positive light is that this occurs in all humans and may be the key to a vast number of human maladies including a vast number of other inflammatory disorders as well as autoimmune diseases, and even cancer.
In addition, the gluten issue aside, whole grain bread has an incredibly high glycemic index and this poses an equally powerful threat to brain health.
What’s your daily diet like? What's currently in your fridge?
I really love to eat and maintain the diet described in Grain Brain. I generally start my day with a three egg omelet made with kale or spinach and covered with olive oil. I drink a cup of coffee with breakfast along with water. At lunch I might have steamed vegetables, salmon, a green salad and an iced tea. And at dinner I again load up with above ground vegetables by themselves or along with wild fish or grass fed beef. I drink one or two glasses of wine each week, but statistically I should drink more. That’s a work in progress.
As to your second question, there’s not much in my fridge at home as we try to keep food as fresh as possible and as of this writing, my wife and I are traveling.

You may have witnessed the short-term effects of food on your brain: a sugar rush after too much candy or a mental fog from hunger. But what we eat also affects us in the long term. Starting in the womb and continuing into old age, our diets don’t just shape our bodies, but our brains as well.

Obesity is associated with significant changes in the brain. In this image, the brain of an obese individual shows fewer dopamine receptors than a control subject. Lower dopamine levels can increase cravings for fatty foods.
Courtesy, with permission: National Institute on Drug Abuse
Poor diets lead to a host of medical issues: obesity, cardiovascular disease, diabetes, and certain cancers. But diet also influences the brain and can increase the risk for mental disorders and neurodegenerative diseases. Researchers are uncovering the details of how the foods we consume affect our cravings, our moods, and even our memories.

Like mother, like child

Food preference first develops in the womb. Studies show that if moms drink carrot juice during pregnancy, infants are more likely to prefer the flavor of carrots. To see if this holds true for less healthy foods and to probe what’s going on in the brain, researchers turned to monkey studies.
While pregnant, monkey mothers ate either a healthy, low-fat diet or a high-fat one. When their offspring were young — equivalent to human toddlers — they were given access to a junk food diet, high in fat and sugar. Compared to monkeys whose mothers ate healthy diets during pregnancy, monkeys whose mothers ate high-fat diets consumed more of the junk food. To see how their prenatal diet had changed their brains and possibly permanently sculpted their food preferences, the researchers looked at the expression of dopamine markers in the brain.  Dopamine is a neurotransmitter important for reward and motivation.
When eating a favorite food, dopamine levels rise, creating that feeling of pleasure experienced by chocolate lovers everywhere. (A similar surge happens with addictive drugs). But eating too many treats leads to a decrease in the effects of dopamine — the brain tries to turn down the signal. Suddenly, it takes more chocolate cake (or cocaine) to feel the same rush.
In the monkeys, prenatal diets high in fat led to a decrease in the number of dopamine fibers and a decrease in dopamine receptors. This could explain why the toddler monkeys gorged on sugary, fatty food: they had to eat more to feel the same pleasure. These findings suggest their brains were primed early on in development to want more junk food.
Heidi Rivera, a postdoctoral researcher at the Oregon National Primate Research Center, points out that the high-fat diet the monkey moms were on is actually “similar to our Western-style diet.” Her results hint at a possible contribution to the soaring childhood obesity rates in the US.

Sugar highs and lows

Rivera’s study shows what you eat during development affects what you want to eat later in life, but Constance Harrell at Emory University wondered, “Can what you eat affect how you feel?”
Data from a 2008 survey revealed that teenagers consume more sugary drinks (sodas, sports drinks, energy drinks, and the like) than people in other age groups. Sugar — especially in the form of high fructose corn syrup, which is now ubiquitous in everything from soda and salad dressing to yogurt and bread — can increase levels of stress hormones in the brain. As adolescence is a crucial time for brain development, high sugar consumption and the subsequent increase in stress hormones during this time may trigger mental health problems, like anxiety and depression.
To see if eating sugar-filled diets affects mental health, Harrell put adolescent rats on either a typical, healthy rodent diet or a diet full of fructose. Compared to the healthy rats, the rats that ate more sugar had higher levels of stress hormones. Next, the researchers tested if the sugar-fed rats were more anxious or depressed.
Indeed, when put in a maze with two kinds of arms — open and exposed or closed and dark — the fructose-fed rats spent more time in the closed, “safe” arms, a sign of increased anxiety. When forced to swim, in a tank of water — something rats don’t particularly enjoy — the fructose-fed rats gave up sooner, indicative of depression. Other studies in adolescent rats have found that sugary diets lead to impaired memory.
“I think it’s important to recognize there are potential impacts for a high fructose diet not only on metabolism, but also on the mind,” says Harrell.

Obesity and memory

Interestingly, adult rats didn’t suffer the same consequences from sugar overload in Harrell’s studies. The developing teenage brain seems to be especially vulnerable to high sugar consumption. However, overall diet — particularly its effect on weight — continues to influence the brain into old age.
For example, some studies have found a link between body weight and the size of the hippocampus, an area of the brain important for learning and memory. Researchers in Australia investigated this link in adults by measuring the size of the hippocampus and comparing it to the person’s body mass index (BMI), a ratio of weight to height that is used to determine if someone is overweight.
They found that, in people in their sixties, those who were overweight or obese (those with the highest BMIs) had smaller hippocampi than people of healthy weights. In addition, over the course of eight years, everyone’s hippocampus shrank, but the overweight subjects experienced the biggest losses. The hippocampus normally shrinks with age, but it shrinks to a greater degree in dementia, which leads to memory problems. Other research in humans suggests that obese people score lower on memory tests, but losing weight through bariatric surgery can improve scores.
Studies in mice might offer some clues about the connection between obesity and the hippocampus. Obese mice had higher levels of inflammation in the brain, including in the hippocampus, caused by the release of a molecule from fat cells. The mice also performed poorly on memory tests, suggesting chronic inflammation wears down the brain, leading to memory problems.
Our brains are sculpted by what we eat. If it’s too much fat, too much sugar, or just too much, there may be permanent consequences for our brain function. Keeping our brains in shape is one more reason to clean up our diets.

Doctors have been saying for years that what you eat can affect the health of your heart. Now there's growing evidence that the same is true for your brain.
A new study by researchers at Rush University Medical Center in Chicago shows a diet plan they developed -- appropriately called the MIND diet -- may reduce the risk of developing Alzheimer's disease by as much as 53 percent.
Even those who didn't stick to the diet perfectly but followed it "moderately well" reduced their risk of Alzheimer's by about a third.
Diet appears to be just one of "many factors that play into who gets the disease," said nutritional epidemiologist Martha Clare Morris, PhD, the lead author of the MIND diet study. Genetics and other factors like smoking, exercise and education also play a role. But the MIND diet helped slow the rate of cognitive decline and protect against Alzheimer's regardless of other risk factors.
The study, published in the journal Alzheimer's & Dementia, looked at more than 900 people between the ages of 58 and 98 who filled out food questionnaires and underwent repeated neurological testing. It found participants whose diets most closely followed the MIND recommendations had a level of cognitive function the equivalent of a person 7.5 years younger.
The MIND diet breaks its recommendations down into 10 "brain healthy food groups" a person should eat and five "unhealthy food groups" to avoid.
It combines many elements of two other popular nutrition plans which have been proven to benefit heart health: the Mediterranean diet and the DASH (Dietary Approaches to Stop Hypertension) diet. (MIND stands for Mediterranean-DASH Intervention for Neurodegenerative Delay.)
But the MIND diet also differs from those plans in a few significant ways and proved more effective than either of them at reducing the risk of Alzheimer's.

The MIND diet recommends frequent servings of green leafy vegetables. Kale, spinach, broccoli, collards and other greens are packed with vitamins A and C and other nutrients. At least two servings a week can help, and researchers found six or more servings a week provide the greatest brain benefits.
The Mediterranean and DASH diets do not specifically recommend these types of vegetables, but the MIND diet study found that including greens in addition to other veggies made a difference in reducing the risk of Alzheimer's.

Like other diets focused on weight loss and heart health, the MIND diet emphasizes the importance of vegetables for brain health. The researchers recommend eating a salad and at least one other vegetable every day to reduce the risk of Alzheimer's.

Nuts are a good snack for brain health, according to the MIND diet study. Nuts contain healthy fats, fiber and antioxidants, and other studies have found they can help lower bad cholesterol and reduce the risk of heart disease. The MIND diet recommends eating nuts at least five times a week.

Berries are the only fruit specifically recommended in the MIND diet. "Blueberries are one of the more potent foods in terms of protecting the brain," Morris said. She noted that strawberries have also shown benefits in past studies looking at the effect of food on cognitive function. The MIND diet recommends eating berries at least twice a week.

If beans aren't a regular part of your diet, they should be. High in fiber and protein, and low in calories and fat, they also help keep your mind sharp as part of the MIND diet. The researchers recommend eating beans three times a week to help reduce the risk of Alzheimer's.

Whole grains are a key component of the MIND diet. It recommends at least three servings a day.

The MIND diet study found eating fish at least once a week helps protect brain function. However, there's no need to go overboard; unlike the Mediterranean diet, which recommends eating fish almost every day, the MIND diet says once a week is enough.

Poultry is another part of a brain-healthy eating plan, according to the MIND diet. It recommends two or more servings a week.

Olive oil beat out other forms of cooking oil and fats in the MIND diet. The researchers found people who used olive oil as their primary oil at home saw greater protection against cognitive decline.

Raise a toast to the MIND diet: it recommends a glass of wine every day. Just one, though.
Wine rounds out the list of of 10 "brain healthy" food groups that help protect against Alzheimer's: green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil and wine.
Now here are the five food groups it says you should avoid to reduce your risk of developing dementia...

Red meat isn't banned in the MIND diet, but the researchers say you should limit consumption to no more than four servings a week to help protect brain health. That's more generous than the Mediterranean diet, which restricts red meat to just one serving a week.

Butter and stick margarine should be limited to less than a tablespoon per day on the MIND diet. Brain-healthy olive oil can often be used instead.

Cheese may be delicious but it doesn't do your brain any favors, according to the MIND diet study. Eat cheese no more than once a week if you want to reduce your risk of Alzheimer's.

You already know they're not so good for your waistline, and it turns out pastries and other sweets could have a negative effect on brain health as well. The MIND diet recommends limiting yourself to no more than five of these treats per week.

Fried foods and fast food round out the MIND diet's list of unhealthy food groups. Limit your indulgence in fried food to no more than once a week for optimal brain health.
But even if you slip up on the diet from time to time, the researchers say it can still have benefits. Even "modest adherence" to the MIND diet measurably reduced a person's chances of developing Alzheimer's disease, and the longer you stick with it, the greater the benefits.
"People who eat this diet consistently over the years get the best protection," said lead author Martha Clare Morris. "You'll be healthier if you've been doing the right thing for a long time."

There's no denying that as we age chronologically, our body ages right along with us. But research is showing that you can increase your chances of maintaining a healthy brain well into your old age if you add these "smart" foods to your daily eating regimen.
Blueberries. "Brainberries" is what Steven Pratt, MD, author of Superfoods Rx: Fourteen Foods Proven to Change Your Life, calls these tasty fruits. Pratt, who is also on staff at Scripps Memorial Hospital in La Jolla, Calif., says that in animal studies researchers have found that blueberries help protect the brain from oxidative stress and may reduce the effects of age-related conditions such as Alzheimer's disease or dementia. Studies have also shown that diets rich in blueberries significantly improved both the learning capacity and motor skills of aging rats, making them mentally equivalent to much younger rats. Ann Kulze, MD, author of Dr. Ann's 10-Step Diet: A Simple Plan for Permanent Weight Loss & Lifelong Vitality, recommends adding at least 1 cup of blueberries a day in any form -- fresh, frozen, or freeze-dried.


Whole Grains: What to Try

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Wild salmon. Deep-water fish, such as salmon, are rich in omega-3 essential fatty acids, which are essential for brain function, says Kulze. Both she and Pratt recommend wild salmon for its "cleanliness" and the fact that it is in plentiful supply. Omega-3s also contain anti-inflammatory substances. Other oily fish that provide the benefits of omega-3s are sardines and herring, says Kulze; she recommends a 4-ounce serving, two to three times a week.
Nuts and seeds. Nuts and seeds are good sources of vitamin E, says Pratt, explaining that higher levels of vitamin E correspond with less cognitive decline as you get older. Add an ounce a day of walnuts, hazelnuts, Brazil nuts, filberts, almonds, cashews, peanuts, sunflower seeds, sesame seeds, flax seed, and unhydrogenated nut butters such as peanut butter, almond butter, and tahini. Raw or roasted doesn't matter, although if you're on a sodium-restricted diet, buy unsalted nuts.
Avocados. Avocados are almost as good as blueberries in promoting brain health, says Pratt. "I don't think the avocado gets its due," agrees Kulze. True, the avocado is a fatty fruit, but, says Kulze, it's a monounsaturated fat, which contributes to healthy blood flow. "And healthy blood flow means a healthy brain," she says. Avocados also lower blood pressure, says Pratt, and as hypertension is a risk factor for the decline in cognitive abilities, a lower blood pressure should promote brain health. Avocados are high in calories, however, so Kulze suggests adding just 1/4 to 1/2 of an avocado to one daily meal as a side dish.
Whole grains. Whole grains, such as oatmeal, whole-grain breads, and brown rice can reduce the risk for heart disease. "Every organ in the body is dependent on blood flow," says Pratt. "If you promote cardiovascular health, you're promoting good flow to the organ system, which includes the brain." While wheat germ is not technically a whole grain, it also goes on Kulze's "superfoods" list because in addition to fiber, it has vitamin E and some omega-3s. Kulze suggests 1/2 cup of whole-grain cereal, 1 slice of bread two-thee times day, or 2 tablespoons of wheat germ a day.
Beans. Beans are "under-recognized" and "economical," says Kulze. They also stabilize glucose (blood sugar) levels. The brain is dependent on glucose for fuel, Kulze explains, and since it can't store the glucose, it relies on a steady stream of energy -- which beans can provide. Any beans will do, says Kulze, but she is especially partial to lentils and black beans and recommends 1/2 cup every day.


Whole Grains: What to Try

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Pomegranate juice. Pomegranate juice (you can eat the fruit itself but with its many tiny seeds, it's not nearly as convenient) offers potent antioxidant benefits, says Kulze, which protect the brain from the damage of free radicals. "Probably no part of the body is more sensitive to the damage from free radicals as the brain," says board-certified neurologist David Perlmutter, MD, author of The Better Brain Book. Citrus fruits and colorful vegetables are also high on Perlmutter's list of "brainy" foods because of their antioxidant properties -- "the more colorful the better," he says. Because pomegranate juice has added sugar (to counteract its natural tartness), you don't want to go overboard, says Kulze; she recommends approximately 2 ounces a day, diluted with spring water or seltzer.
Freshly brewed tea. Two to three cups a day of freshly brewed tea -- hot or iced -- contains a modest amount of caffeine which, when used "judiciously," says Kulze -- can boost brain power by enhancing memory, focus, and mood. Tea also has potent antioxidants, especially the class known as catechines, which promotes healthy blood flow. Bottled or powdered teas don't do the trick, however, says Kulze. "It has to be freshly brewed." Tea bags do count, however.
Dark chocolate. Let's end with the good stuff. Dark chocolate has powerful antioxidant properties, contains several natural stimulants, including caffeine, which enhance focus and concentration, and stimulates the production of endorphins, which helps improve mood. One-half ounce to 1 ounce a day will provide all the benefits you need, says Kulze. This is one "superfood" where more is not better. "You have to do this one in moderation," says Kulze.
 

 

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