Nourishing the Developing Brain

In 1987, pediatricians at North Shore University Hospital in Manhasset, New York, faced an unusual situation. In a thriving middle class community, they were suddenly called to treat seven infants who were definitely not thriving, meaning that the babies’ bodies and, more disturbing, their brains were not developing as expected.

Failure to thrive is commonly linked to malnutrition. And, in an unusual way, this failure turned out to be the case. After a series of diagnostic exams and questions, the Long Island doctors discovered that seven sets of nutrition-conscious parents had been feeding their children a low-fat, low-cholesterol diet meant to protect adults at risk of heart disease.

Happily, the doctors changed the diet, the infants recovered, and everybody got the point: Not only does a developing brain need plenty of calories, but also a lot of those calories should come from fats, particularly the polyunsaturated omaga-3 fatty acid, docosahexanoic acid, better known as DHA.

Fats and the fetal brain

The human body is about 60 percent water. The human brain is about 60 percent fat, and most of that is DHA. This fatty acid is vital for the proper functioning of the adult brain but even more important for the development of the fetal brain and spinal cord. (Consuming foods with DHA also helps reduce the risk of cardiovascular disease, but that’s a story for another chapter or another book, perhaps check out Controlling Cholesterol For Dummies, which I coauthored with Martin W. Graf, MD [Wiley].)

More than 20 years after the seven fat-deprived babies showed up at North Shore, an entire catalog of well-designed studies has documented the advantages conferred on infants whose mothers get plenty of DHA — the best source is fish oils, fish, and seafood (see Table 24-2, later in this chapter) while pregnant — along with all the normal vitamins, minerals, and other essential components of a healthful diet, of course.

Right from the start, babies delivered by women with higher blood levels of DHA are more attentive to new stimuli. For the next six months, they score higher on tests of cognition (thinking processes) than babies born to women with lower levels of DHA. According to one report from Harvard Medical School, by the time the DHA-enriched babies are 3 years old, they may also score several points higher on vocabulary tests.

But DHA’s brain benefit doesn’t end with babies.

Fish and the teenage brain

The next time your teen brother, nephew, son, or friend tells you he’s a grown-up, smile pleasantly and hand him a tuna sandwich. In fact, the brain of an older teen — think 15, 16, 17, and 18 — is particularly “plastic,” meaning particularly able to build the new connections required to learn new things like high-school math, science, history, and literature.

In 2009, scientists at Sweden’s Gothenburg University reported that 15-year-old boys who eat fish more than once a week score higher on intelligence tests than their non-fish-eating friends.

Not being totally chauvinistic, the Gothenburg researchers soon filed another report, this one on teenage females. Sure enough, those who ate fish did better in school. So when you’re serving tuna on rye, make sure your teen brother, nephew, son, or friend shares that tuna sandwich with his sister, niece, or girlfriend. And vice versa.

Determining how much DHA a body needs

In 2002, the National Academy of Science’s Food and Nutrition Board set recommendations for daily consumption of omega-3 fatty acids, as shown in Table 24-1. By the way, as I explain in Chapter 3, the Adequate Intake (AI) is a recommendation for nutrients for which there is no Recommended Dietary Allowance (RDA).

Table 24-1 Daily Adequate Intake (AI) for Omega-3s

	Age	Adequate Intake (AI)
Infants	0–12 months	0.6 g/600 mg
Children	1–3 years	0.7 g/700 mg
	4–8 years	0.9 g/900 mg
	9–13 years	1.2 g/1,200 mg
	14–18 years	1.6 g/1,600 mg (boys)
		1.1 g/1,100 mg (girls)
Pregnant women		1.4 g/1,400 mg
Breast feeding women		1.3 g/1,300mg
Adults	19+	1.6 g/1,600 mg (men)
		1.1 g/1,100 mg (women)

Food and Nutrition Board, National Academy of Sciences, “Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids,” September 5, 2002

Avoiding malicious mercury

Naturally, there is a catch in the day’s catch. Some fish contain an unhealthful amount of methylmercury, a compound produced by bacteria that chemically alter the naturally occurring mercury in rock and soil or the mercury released into water through industrial pollution.

Little fish eat mercury-contaminated algae, bigger fish eat the smaller fish, people eat the bigger fish, and the mercury ends up there. The larger the fish and the longer it lives, the higher its mercury content is likely to be. To reduce the risk to fetal development, the 2015–2020 Dietary Guidelines for Americans advisory committee advises pregnant woman to avoid the Mercury Big Four (shark, swordfish, king mackerel, and tilefish) and limit their weekly consumption of seafood to two or less 4-ounce servings of seafood high in omega-3s and low in mercury.

Luckily, you can also get DHA from foods other than fish. For example, many infant formulas now contain DHA derived from fermented algae, and health-food stores sell algae-based DHA supplements for adults. One plain egg yolk contains 20 milligrams/0.02 grams of DHA; an egg yolk from an egg laid by a hen fed a DHA-enriched diet may contain up to 200 milligrams/0.2 grams of DHA. Some nuts and seeds (think walnuts and flaxseed) contain alpha linolenic acid, a precursor converted by our bodies to DHA.

Table 24-2 shows the DHA and mercury content of some popular fish and shellfish.

Table 24-2 DHA & Mercury Content of Popular Fish & Seafood

Fish	Grams of DHA per 100 g/3.5 oz	Mercury Content*
Anchovy	1.3	Low
Catfish	0.13	Low
Clams	0.15	Not detectible
King mackerel	0.23	High
Salmon, Atlantic, wild Salmon, Atlantic, farmed	1.43 0.62	Low Low
Sardine, canned, drained	0.51	Low
Scallop	0.10	Low
Shark, raw	0.53	High
Swordfish	0.68	High
Tilefish	0.73	High
Trout, mixed species	0.68	Low

* Low = less than 0.12 ppm; high = more than 0.730 ppm.

USDA, Appendix G2: Original Food Guide Pyramid Patterns and Descriptions of USDA Analyses, Addition A: EPA and DHA Content of Fish Species, 2005; FDA, Mercury Levels in Commercial Fish and Shellfish, 2006

Protecting the Adult Brain

Once upon a time, people thought that as soon as you and your brain were born, that was the end of making new neurons and that barring illness or injury, what you had, structurally speaking, was pretty much what you would have until “The End.” Today, a growing body of evidence suggests that may be partially a fairy tale.

In the last decade, several studies at institutions as diverse as the University of Victoria (Canada), the University of Hong Kong, the University of Cambridge (Great Britain), and the U.S. National Institute on Aging point to the conclusion that important areas of the brain, such as the hippocampus — the site of memory, learning, and emotion — continue to generate new cells. And guess what? The same exercise that tones your abs may tone your brain. In experiments with rats, scientists have found that the little critters who run about the most produce the most new cells.

We all know that a brisk run in the park can clear cobwebs from an overworked brain, but will it also make new cells for our human brains? While we’re waiting to find out, you can and certainly should use your full-grown brain to learn new things. And regardless of age, you can strive to protect and preserve your intellectual brain functions: cognition (the processes of learning, thinking, and reasoning) and memory (the ability to retain and recall past experiences).

REMEMBER THIS

Short-term memory lasts a few minutes. If you are reading a book, and you put it down to answer the phone, short-term memory enables you to go back and recognize where you left off. Or to remember a strange phone number long enough to dial it.

Long-term memory lasts for years. If what you were reading strikes a chord, you may store it in your brain and pull it out from time to time. For example, few people who read Charles Dickens’s A Tale of Two Cities ever forget the first two lines: “It was the best of times. It was the worst of times.” Or, on a more practical level, their own phone numbers.

Amnesia is loss of memory related to an illness or an injury. Retrograde amnesia is the inability to remember things that happened before the illness or injury; anterograde amnesia is the inability to form new memories afterward. With the former, you can’t remember the phone number you had in high school. With the latter, you won’t be able to remember the new phone number you might get tomorrow.

Introducing the natural enemies of thought and memory

The old news was that after a certain age, say, 30, your brain begins to shrink until it simply shrivels into nothing. But, as noted earlier, scientists who have actually taken the time to sit down and count brain cells find practically no age-related loss of those hippocampal cells responsible for cognition and memory. However, the cells in your adult brain — like other body cells — do face two natural enemies: oxidative stress and inflammation.

Oxidative stress is damage done by particles called free radicals that form during chemical reactions occurring in the body. As you grow older, your cells’ sensitivity to this kind of injury goes up while your ability to heal afterward goes down.
Inflammation is your immune system’s natural response to injury: swelling, heat, and pain. The American Heart Association regards C-reactive protein (CRP), a protein whose presence increases during inflammation, as a risk factor for heart disease and stroke. A natural increase in the level of tumor necrosis factor alpha and interleukin-6, two inflammatory agents in your brain and spinal cord, appears to play a role in the age-related loss of both cognition and memory.

How do you counter these two enemies? One possibility: nutrition.

ARE VITAMINS VITAL?

Using nutritional supplements to boost brain power is an iffy proposition, long on theory and short on proof.

True, deficiencies of specific nutrients, such as iron, can adversely affect brain development and function. For example, in 1996, researchers at Johns Hopkins Children's Center recruited iron-deficient but not-yet-anemic high-school girls from four Baltimore high schools, gave them iron supplements, and watched their test scores rise.

But do supplements increase brain health for healthy people? Yes. No. And maybe — the evidence is far from conclusive. As for herbs, such as ginko biloba, ginseng, and gotu kola — is there something special in plants beginning with the letter g? — they come into vogue and then slide out again as scientific studies show a lack of effect.

The best advice on nutrients for your brain is to always stick to that boring but effective varied diet, beating the belly to keep your brain in shape.

Dieting to keep your brain in shape

The human body stores extra fat in several well-defined places, and as the body ages, these fat deposits tend to expand. For women, it’s hips and thighs. For men, it’s shoulders and the abdomen, the large area between chest and pelvis commonly known as the belly. Simple observation shows that men are more likely than women to have big bellies, particularly as they grow older. But belly fat may be hazardous to brain health for both genders, even when the body with the belly isn’t overweight and its BMI (the body mass index described in Chapter 4) is within normal range.

In 2008, data from a Kaiser Permanente study of nearly 7,000 volunteers, age 40 to 45, showed that people with big bellies are more likely than those with flat tummies to develop Alzheimer’s later in life. One theory to explain this is that belly fat sends damaging molecules through the bloodstream to the brain, but the true link is still a true mystery. Or as one nutrition researcher elegantly puts it, “An exciting area that needs to be explored.”

As Chapter 4 explains, healthy bodies come in all sizes and shapes. Holding to a brain-healthy shape definitely doesn’t mean dieting to skeleton size. Doing that deprives your brain (and the rest of your body) of essential nutrients. In short, a sensible diet leads to a sensible body and a sensible brain

Choosing foods that boost the brain

Plants are deceptive. On the outside, they’re mostly green and calm. On the inside, they’re busy little chemical factories churning out multitudinous compounds, many of which have properties that protect the plant — and various parts of your body, including, of course, your brain.

One class of these natural chemicals is the polyphenols, so named because their molecules are built of many (poly-) ring-shape (phenol) components. Polyphenols are widely distributed in fruits and vegetables as well as in nuts, seeds, and grains. Some have antioxidant, antiallergic, anti-inflammatory, antiviral, or antiproliferative (prevents cell from irregular reproduction, an anticancer trait) effects.

One group of important antioxidant and anti-inflammatory polyphenols are the flavonoids (sometimes incorrectly spelled flavanoids), the pigments that color plants yellow, red, orange, green, or white. Some flavonoids may also be antiviral and antiproliferative. Altogether, flavonoids protect plants from oxidative stress, including stress triggered by attacks from insects, fungi, and microbes.

Experimenting with antioxidants

Tests performed on living animals are called in vivo, from the Latin word for “life”; those done in test tubes are called in vitro, from the Latin word for “glass.” During in vitro experiments, some flavonoids have shown even more powerful antioxidant effects than the antioxidant vitamins C and E, thus providing a scientific rationale for the possibility that to protect the brain you should choose your diet by color, opting always for the most brilliant fruits and vegetables.

In 1994, two scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston drew up a scale ranking foods according to their Oxygen Radical Absorbency Capability (ORAC) — in other words, their ability to protect against oxidative damage to body cells, including brain cells. For a while, USDA posted the ORAC food list on its official site. But with increasing evidence that a high ORAC score may not actually correlate with a protective effect, the list was removed in 2010. Nonetheless, fruits and veggies are clearly good for the human body, so the advice to eat your several servings of fruits and veggies a day remains NSOP (nutrition standard operating procedure, of course).

TWO TASTY EXCEPTIONS

Despite doubts about the ORAC list, two foods that seem to fulfill their promise as brain-friendly antioxidants are cocoa powder and blueberries.

A continuing series of American and European studies from 2008 on attest to flavonoid-rich cocoa powder’s ability to enhance cognition and memory. For example, a 2015 report in the American Journal of Clinical Nutrition notes that when Italian researchers asked 90 healthy, dementia-free senior citizens, age 60 to 85, to drink specially prepared cocoa every day for eight weeks, those who got cocoa with lots of flavonoids scored better on tests measuring memory and attention span than did those who got medium- or low-flavonoid cocoa. American Journal of Clinical Nutrition published a result echoing a 2006 study in which cocoa not only improved cognition but also lowered blood pressure.

Blueberries have also been proven brain-friendly. In January 2010, a team of researchers from the University of Cincinnati, the USDA, and the Canadian Department of Agriculture released data from a study in which volunteers in their 70s exhibiting early symptoms of memory loss were given either the equivalent of 2 to 2½ cups of blueberry juice or a lookalike substitute every day for two months. When the testing ended, the blueberry people had improved their performance on memory tests; the lookalike group had not. (See the section “Minding your mind diet” for more on blueberries.)

Minding your mind diet

If there is one — no, two — diets on whose virtues every reputable expert agrees, it’s the Mediterranean diet and DASH, also known as Dietary Approaches to Stop Hypertension. Both diets, built on a base of plant foods plus low-fat, protein-rich foods, such as fish and poultry, are known to reduce the risk of cardiovascular disease. Now Martha Clare Morris, a nutritional epidemiologist at Rush Alzheimer’s Disease Center in Chicago, has put them together to create the MIND diet, short for Mediterranean-DASH Intervention for Neurodegenerative Delay, a mouthful in itself.

The MIND diet has 15 food categories: 10 are brain-healthy; 5, not so much.

The ten “good” foods are

Berries
Beans
Fish
Nuts
Olive oil
Poultry
Vegetables (green leafy)
Vegetables (everything else)
Whole grains
Wine

The five “not so good” foods are

Butter and stick margarine
Cheese
Fried or fast food
Pastries and sweets
Red meats

Overall, the MIND diet provides three servings of whole grains, one salad (those leaves), and one more vegetable a day, beans every other day, poultry and berries at least twice a week, and fish at least once. The recommended snack is nuts. And, yes, a glass of wine to top off every day’s delights.

As for those other foods, less than a tablespoon of butter or stick margarine a day, less than one serving of fried or fast food a week (presumably, fast-food salads meet muster).

Does it work? The best proof that the Rush people can offer is the result of their five-year-long study of 960 adults average age 81 and older who were dementia-free at the start. Participants were asked to fill out food questionnaires, listing what they ate and how often they chose various foods. Each year, they were given standardized tests of memory and their ability to interpret and act on visual cues. At the end, according to a report in Alzheimer’s & Dementia, the journal of the Alzheimer’s Association, those who followed the MIND diet to the letter reduced their risk of Alzheimer's by as much as 53 percent; those who sort of followed the diet reduced their risk by about 35 percent.

Altering the Emotional Brain

A mood is a feeling, an internal emotional state that can affect how you see the world. If your team wins the World Series, your happiness may last for days, making you feel so mellow that you simply shrug off minor annoyances, such as finding a ticket on your windshield because your parking meter expired while you were having lunch. If you’re sad because the project you spent six months setting up didn’t work out, your disappointment can linger long enough to make your work seem temporarily unrewarding or your favorite television sitcom totally unfunny.

Most of the time, after shifting one way or the other, your mood swings back to center fairly soon. You come down from your high or recover from your disappointment, and life resumes its normal pace — some good news here, some bad news there, but all in all, a relatively level field.

Occasionally, however, your mood may go haywire. Your happiness over your team’s victory escalates to the point where you find yourself rushing from store to store buying things you can’t afford, or your sadness over your failure at work deepens into a gloom that steals joy from everything else. This unpleasant state of affairs — a mood out of control — is called a mood disorder.

Recognizing mood malfunctions

Approximately one in every four human beings (more frequently a woman than a man) experiences some form of mood disturbance during his or her lifetime. Eight or 9 out of every 100 people will experience a clinical mood disorder, a mood disorder serious enough to be diagnosed as a disease.

The two most common moods are happiness and sadness. The two most common mood disorders are clinical depression, an elongated period of overly intense sadness, and clinical mania, an elongated period of overly intense elation. Clinical depression alone is called a unipolar (one-part) disorder; clinical depression plus clinical mania is a bipolar (two-part) disorder.

Natural chemicals that affect mood

Your body makes a group of substances called neurotransmitters, which are chemicals that enable brain cells to send messages back and forth. Three important neurotransmitters are

Dopamine (doe-pa-meen)
Norepinephrine (nor-e-pe-nef-rin)
Serotonin (ser-a-toe-nin)

Dopamine and norepinephrine are chemicals that make you feel alert and energized. Serotonin is a chemical that can make you feel smooth and calm. Some forms of clinical depression appear to be a malfunction of the body’s ability to handle these neurotransmitters effectively.

Mood meds

Several medical drugs are useful in making neurotransmitters more available to your brain or enabling your brain to use them more efficiently. These medications include

Tricyclic antidepressants: These drugs were the first truly effective antidepressants. They’re named for their chemical structure: three ring-shaped groups of atoms (tri = three; cyclic = ring). They relieve symptoms by increasing the availability of serotonin. One well-known tricyclic is amitriptyline (Elavil).
Monoamine oxidase inhibitors (MAO inhibitors): These drugs interrupt the actions of an enzyme that triggers the natural elimination of dopamine and other neurotransmitters so that they remain available for your brain. Phenelzine (Nardil) and tranylcypromine (Parnate) are MAO inhibitors.
Selective serotonin reuptake inhibitors (SSRIs): These medicines slow the body’s natural reabsorption of serotonin, leaving more serotonin available to your brain. Celexa (citalopram), Lexapro (escitalopram oxalate), Luvox (fluoxamine), Paxil (paroxetie), Prozac (fluoxetine), and Zoloft (sertraline) are SSRIs.
Selective serotonin-norepinephrine reuptake inhibitors (SNRIs): These medicines slow the body’s natural reabsorption of both serotonin and norepinephrine. Cymbalta (duloxetine), Effexor (venlafaxine), and Priztiq (desvenlafaxine) are SNRIs.
Norepinephrine and dopamine reuptake inhibitor (NDRI): This medicine slows the body’s natural reabsorption of norepinephrine and dopamine. Wellbutrin (buproprion) is an NDRI. Note: Buproprion is also marketed as an antismoking drug under the brand name Zyban.

Seeing how food can affect your mood

Good morning: Time to wake up, roll out of bed, and sleepwalk into the kitchen for a cup of coffee.

Good afternoon: Time for a moderate glass of whiskey or wine to soothe away the tensions of the day.

Good grief: Your lover has left. Time for chocolate, lots of chocolate, to soothe the pain.

Good night: Time for milk and cookies to ease your way to Dreamland.

For centuries, millions of people have used these foods in these situations, secure in the knowledge that each food will work its mood magic. Today, modern science knows why. Having discovered that your emotions are linked to your production or use of neurotransmitters, nutrition scientists have been able to identify the natural chemicals in food that change the way you feel by

Influencing the production of neurotransmitters
Hooking onto brain cells and changing the way the cells behave
Opening pathways to brain cells so that other mood-altering chemicals can come on board

The following sections describe chemicals in food commonly known to affect mood.

Alcohol

Alcohol is man’s (and woman’s) most widely used natural relaxant. Contrary to common belief, alcohol is a depressant, not a mood elevator. If you feel relaxed or, conversely, exuberant after one drink, the reason isn’t that the alcohol is speeding up your brain; it’s that alcohol loosens your controls, the brain signals that normally tell you not to put a lampshade on your head or take off your clothes in public.

For more about alcohol’s effects on virtually every body organ and system, turn to Chapter 9. Right here, it’s enough to say that many people find that, taken with food and in moderation — defined as one drink a day for a woman and two for a man — alcohol can comfortably change a mood from tense to mellow.

Anandamide

Anandamide is a cannabinoid, a chemical that hooks up to the same brain receptors that catch similar ingredients in marijuana smoke. Your brain produces some anandamide naturally, but you also get very small amounts of the chemical from cocoa bean products — chocolate. In addition, chocolate contains two chemicals similar to anandamide that slow the breakdown of the anandamide produced in your brain, thus intensifying its effects.

Maybe that’s why eating chocolate makes you feel so good. And that really does mean mildly: You’d have to eat at least 25 pounds of chocolate at one time to get any marijuanalike effect. In 2009, a team of nutrition scientists at the Nestle Research Center in Lausanne (Switzerland) produced the still-classic study of the beneficial calming effects. Their results put the amount required to reduce the body’s production of stress hormones at 40 grams (about 1.5 ounces) of dark chocolate a day. The chocolate used in the study was 74 percent cocoa, served in two daily doses, 20 grams in the morning and 20 grams in the afternoon, after which the researchers tested the volunteers’ blood to measure levels of stress hormones and found the levels of stress hormones dropping among the chocolate eaters, thus making chocoholics everywhere even happier than usual.

Caffeine

Caffeine is a mild stimulant that

Raises your blood pressure
Speeds up your heartbeat
Makes you burn calories faster
Makes you urinate more frequently
Causes your intestinal tract to move food more quickly through your body

Although it increases the level of serotonin, the calming neurotransmitter, caffeine also hooks up at specific receptors (sites on the surface of brain cells) normally reserved for another naturally occurring tranquilizer, adenosine (a-den-o-seen). When caffeine latches on in place of adenosine, brain cells become more reactive to stimulants such as noise and light, making you talk faster and think faster.

But caffeine can be confusing. People react to it in highly individual ways. Some can drink seven cups of regular (“with caffeine”) coffee and still stay calm all day and sleep like a baby at night. Others tend to hop about on decaf. Perhaps those who stay calm have enough brain receptors to accommodate both adenosine and caffeine, or perhaps they’re more sensitive to the adenosine that manages to hook up to brain cells. Nobody really knows. Either way, caffeine’s bouncy effects may last anywhere from one to seven hours.

Table 24-3 lists some common food sources of caffeine. The caffeine content listed here is an average for the generic versions of the food or drink — in other words, plain, no-brand products. You can check out the caffeine content of brand-name products such as a Starbucks Espresso Solo (75 mg/oz) or Ben & Jerry’s coffee flavored ice cream (34 mg/4 oz) at the Center for Science in the Public Interest website at www.cspinet.org/new/cafchart.htm.

Table 24-3 Foods That Give You Caffeine

Food	Average Amount of Caffeine (mg)
6-ounce cups
Coffee, regular, drip	71
Coffee, regular, instant	47
Coffee, decaffeinated	1
Tea	36
Tea, instant	20
Cocoa (mix + water)	4
12-ounce can
Soft drinks, cola	29
8-ounce container
Chocolate milk (commercial, low-fat)	5
1-ounce serving
Milk chocolate	6
Semisweet chocolate	24
Bitter (baker’s) chocolate	23

USDA National Nutrient Database for Standard Reference, www.nal.usda.gov/fnic/foodcomp/search

Tryptophan and glucose

Tryptophan is an amino acid, another one of those “building blocks of protein” (see Chapter 6). Glucose, the end product of carbohydrate metabolism, is the sugar that circulates in your blood, the basic fuel on which your body runs (see Chapter 8). Milk and cookies, a classic calming combo, owe their power to the tryptophan/glucose team.

Start with the fact that the neurotransmitters dopamine, norepinephrine, and serotonin are made from the amino acids tyrosine and tryptophan, which are found in protein foods (like milk). Tyrosine is the most important ingredient in dopamine and norepinephrine, the alertness neurotransmitters. Tryptophan is the most important ingredient in serotonin, the calming neurotransmitter.

All amino acids ride into your brain on chemical pathways, but your brain makes way for the bouncy tyrosine first and the soothing tryptophan last. That’s why a high-protein meal heightens your alertness.

To move the tryptophan along faster, you need glucose, and that means carbohydrate foods (like those cookies). When you eat carbs, your pancreas releases insulin, a hormone that enables you to metabolize the carbs and produce glucose. The insulin also keeps tyrosine and other amino acids circulating in your blood so that tryptophan travels on plenty of open paths to the brain. With more tryptophan coming in, your brain can increase its production of soothing serotonin. That’s why a meal of starchy pasta (starch is composed of chains of glucose molecules, as explained in Chapter 8) makes you feel calm and cool.

The effects of simple sugars, such as sucrose (table sugar), are more complicated. If you eat simple sugars on an empty stomach, the sugars are absorbed rapidly, triggering an equally rapid increase in the secretion of insulin, a hormone needed to digest carbohydrates. The result is a rapid decrease in the amount of sugar circulating in your blood, a condition known as hypoglycemia (hypo = low; glycemia = sugar in the blood) that can make you feel temporarily jumpy rather than calm. However, when eaten on a full stomach — dessert after a full meal — simple sugars are absorbed more slowly and may exert the calming effect usually linked to complex carbohydrates (starchy foods).

Obvious conclusion: Some foods, such as meat, fish, and poultry, make you more alert. Others, such as pasta, bread, potatoes, rice, and other grains, calm you down. The effect of the food depends on its ability to alter the amount of serotonin available to your brain (see Figure 24-1).

© *John Wiley & Son, Ltd*

FIGURE 24-1: Some foods may calm you, and some foods may make you more alert.

Fascinating factoid: Even though turkey is high in protein, it’s also high in tryptophan, the precursor of (that is, the chemical that leads to the creation of) serotonin, which may explain why so many people nod off after Thanksgiving dinner.

Phenylethylamine (PEA)

Phenylethylamine — sometimes abbreviated PEA — is a natural chemical that your body releases when you’re in love, making you feel, well, good all over. A big splash occurred in the late 1980s when researchers discovered that chocolate, the food of lovers, is a fine source of PEA.

In fact, many people think that PEA has a lot to do with chocolate’s reputation as the food of love and consolation. Of course, to be fair about it, chocolate also contains the mood-elevator caffeine, the muscle stimulant theobromine, and the cannabinoid anandamide (see the earlier section on anandamide).

Using food to manage mood

No food will change your personality or alter the course of a mood disorder. But some may add a little lift or a small moment of calm to your day, increase your effectiveness at certain tasks, make you more alert, or give you a neat little push over the finish line.

The watchword is balance:

One cup of coffee in the morning is a pleasant push into alertness. Seven cups of coffee a day can make your hands shake.
One alcohol drink is generally a safe way to relax. Three may be a disaster.
A grilled chicken breast (white meat, no skin) for breakfast on a day when you have to be on your toes before lunch can help make you sharp as a tack.
Got an important lunch meeting? Order starches without fats or oils: pasta with fresh tomatoes and basil, no oil, no cheese; rice with veggies; rice with fruit. Your aim is to get the calming carbs without the high-fat food that slows thinking and makes you feel sleepy.

As in other aspects of a healthy life, the point is to make sure that you use the tool (in this case, food), not the other way around.

CAUTION! MEDICINE AT WORK

Some of the mood-altering chemicals in food interact with medicines. As you may have guessed, the two most notable examples are caffeine and alcohol.

Caffeine makes painkillers, such as aspirin and acetaminophen, more effective. On the other hand, many over-the-counter (OTC) painkillers and cold medicines already contain caffeine. If you take the pill with a cup of java, you may increase your caffeine intake past the jitters stage.
Alcohol is a no-no with most medicines because it increases the sedative or depressant effects of some drugs, such as antihistamines and painkillers, and alters the rate at which you absorb or excrete others.

Always ask your pharmacist about food-drug interactions (you can read more about this in Chapter 25) when you fill a prescription or purchase an OTC product.

Healing the Injured Brain

Slice off your finger while chopping wood, and as you’re on the way to the emergency room, some helpful passerby can pick up the finger, hopefully stick it into a cup of ice to chill and preserve the tissues, and dawdle his way over to the hospital to meet you. If the finger arrives within a couple of hours, it likely can be successfully reimplanted. New cells will grow to heal the damage. Blood will flow through reattached vessels. Newly stitched nerves and muscles will signal and move. Bones will knit together. And you may well enjoy a working five-fingered hand.

But hit your head hard enough to injure brain cells, suffer a stroke, or have a heart attack that interrupts the flow of oxygenated blood to the brain, and your brain cells begin to die within minutes.

To reduce the loss of brain cells and limit damage to an injured brain, doctors concentrate on ensuring an adequate supply of oxygen and controlling swelling that pushes the soft brain against the inside of the hard skull.

But there may be another weapon in the arsenal: food.

The 5, 7, 2, 4, 100, 200 solution

After any injury, your body goes into a hypermetabolic state (hyper is the Greek word for “over”), meaning that it suddenly requires more calories than normal to provide the energy and material to rebuild damaged tissues. True, an injured brain won’t be producing new cells, but this 2 percent of your weight that consumes 20 percent of your calorie intake will need extra energy to establish the new connections that can enable you to function.

In fact, feeding patients with brain injuries is so important that neurologists at Presbyterian Hospital/Weill Cornell Medical Center in New York have actually put some hard numbers to it: 5, 7, 2, 4, 100, 200.

Translation: Patients with brain injury who are not fed either intravenously or through a tube into the stomach within 5 days after the injury occurs are 2 times more likely to die than are patients who get fed. Patients not fed within 7 days are 4 times more likely to die. And the best menu provides 100 percent of the normal recommended daily calories for that particular patient (see Chapter 3); up to 200 percent is even better.

“There is no miracle drug for patients with severe traumatic brain injury,” says Roger Härtl, director of neurotrauma at the Brain and Spine Center of Weill Cornell Medical College. “But we have been able to reduce the mortality and improve outcome in these patients dramatically over the past 15 years by maintaining their blood pressure and supplying the brain early on with oxygen and nutrients. We now start feeding patients with severe brain injuries very aggressively from the moment they first hit the intensive care unit, and early nutrition is now recognized as one of the most important factors improving outcome in these patients.” So important, in fact, that the regimen has now been incorporated in the international Guidelines for Management of Severe Traumatic Brain injury.

Protein possibilities

Leucine, isoleucine, and valine are amino acids, the building blocks of protein described in Chapter 6. Because these three particular amino acids share a distinct chemical structure — a long central chain with smaller side chains branching off — they’re called branched chain amino acids (BCAA, for short).

The body uses BCAA to build neurotransmitters, the naturally occurring chemicals that enable cells to exchange messages: Think! Move! Feel! Unfortunately, an injury to the brain that damages the hippocampus, a part of the brain that helps direct memory and cognition, may reduce brain levels of leucine, isoleucine, and valine.

As long ago as 1983, studies suggested that intravenous doses of BCAA would benefit patients with liver disease by forcing additional amino acids into their brain. Some sports nutritionists think that BCAA supplements can improve muscle performance.

Neuroscientist Akiva Cohen and his team at The Children’s Hospital of Philadelphia see a more direct application. When they added BCAA to the drinking water of brain-injured mice, Cohen’s team observed improvements in both mouse memory and cognition. If future studies with human beings demonstrate the same effect, patients with traumatic brain injuries might be able to avoid the feeding tubes and intravenous needles to improve their thinking and remembering simply by sipping a glass of branched-chain-amino-acid-enriched (building blocks of protein) water. A follow-up study in 2013 showed that the amino acids also improve “wakefulness” — the ability to stay awake and alert — after traumatic brain injury (TBI), thus enhancing recovery.

The (eventual) official word

Because military personnel, especially those in combat zones, face a distinct risk of TBI, in 2009, the Department of Defense (DoD) asked the Institute of Medicine (IOM) to convene an expert committee to review the potential role of nutrition in the treatment of and resilience against TBI.

The IOM is the division of the National Academy of Sciences that sets and publishes the RDAs, RDIs, and other nutritional recommendations listed in Chapter 3. To meet the DoD request, IOM set up a Consensus Study on Nutrition, Trauma, and the Brain to determine “the potential role for nutrition in providing resilience (i.e., protecting), mitigating or treating of primary (i.e., within minutes of insult), secondary (i.e., within 24 hours of insult), and long-term (i.e., more than 24 hours after insult) associated effects of neurotrauma, with a focus on traumatic brain injury.”

Two years later, in 2011, IOM issued a first report from the study. The primary message, an echo of Dr. Härtl’s (see the earlier section “The 5, 7, 2, 4, 100, 200 solution”): All military personnel suffering from traumatic brain injury should get adequate protein and calories as soon as possible to reduce inflammation and improve their recovery and eventual outcome. This advice, they noted, also applied for non-military people, such as athletes, who were at risk of concussion and other brain injuries.

Brain Food