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Sweet Nothings:
The Sugar Seduction

 

Here is how to magnetize a baby: Start with a calm infant of nine to twelve weeks of age. Sit face to face, about fifteen inches apart. Dip a pacifier into sugar water (made by stirring a teaspoon of sugar into a cup of water) and put the pacifier in the baby’s mouth. If it falls out, dip it again and put it back. Keep it there for three and one-half minutes while maintaining consistent eye contact. That’s all it takes. You can then leave the room. When you return, you will find that the baby will look at you, smile, gurgle, and maybe even throw you a coy expression. He or she will follow you with his or her eyes and clearly prefer you over other people. What you have done is to register your face in the baby’s memory and connect that image with a sensation in the baby’s pleasure circuitry, triggered by sugar. The effect is temporary, lasting for several minutes rather than hours or days, but it is quite noticeable.

Researchers at the University of Massachusetts at Amherst pioneered this peculiar sort of experiment.¹ Apart from its practical value for grandparents, aunts, and uncles, these studies have allowed scientists to explore sugar’s druglike effects, as we’ll see in this chapter. But we’re getting ahead of ourselves. Let’s start at the beginning.

 

Hooked on Sugar

 

An enormous number of people feel hooked on “carbohydrates.” They are drawn to cookies, cake, bread, potato chips, and french fries. But the truth is, what they are hooked on is not carbohydrate at all—at least, not in the way that scientists use that term. After all, there is carbohydrate—that is, starch—in green vegetables, fruits, and beans, too, yet virtually no one is “hooked” on them.

What so-called “carbohydrate addicts” are really hooked on is sugar.² In essentially every case, the carbohydrates people crave are those that are either loaded with sugar—like doughnuts and cookies—or that rapidly disintegrate into millions of sugar molecules that rush into the bloodstream during the process of digestion. White bread, potatoes, and, of course, anything with sugar itself in it, are the foods that cause a blood sugar spike, and they are the ones people crave. Unfortunately, on the heels of that blood sugar spike comes a rapid blood sugar drop that can spark a quick return of appetite. And that means a trip back to the fridge for more cookies or cake, or a rush to the nearest doughnut shop. These foods usually have fat—shortening in cookies, or butter on bread—mixed in, too, and the combination causes a pronounced opiate effect, as we’ll see shortly.

Most other carbohydrate-rich foods—the healthy choices, including vegetables, beans, and most whole grains—are different. Yes, they will eventually release sugars in the course of digestion, but they do so slowly, in precisely the form your body uses for energy. There is nothing wrong with these starchy foods. In fact, without them you would not have the normal fuel you need for an active life, let alone any sort of athletic endeavor.

The finger of blame, if there is one, ought to point at sugar. That’s what gets us hooked and what adds lots of unnecessary calories. Candy counters, soda machines, and convenience store displays all offer sticky treats. And certain kinds of bread, potatoes, and cookies can be sugar bombs, too, propelling late-night binges. Now, there are also healthy choices when it comes to bread and potatoes, and, in this chapter, we’ll sort out which are which.

Norma, one of our research participants, felt really hooked. “Once I start, I can’t stop,” she said. Bread, cookies, and crackers seemed to have no limit, and distractions, like television, only aggravated the problem. Sitting in front of a favorite program, she would easily lose track of how much she had eaten. “Before I know it, I’ve eaten a whole pack of cookies, and I’m still looking for more.” Despite other improvements in her diet, her weight-loss efforts were stalled.

 

In essentially every case, the “carbohydrates” people crave are those that are either loaded with sugar—like doughnuts and cookies—or that rapidly disintegrate into millions of sugar molecules that rush into the bloodstream.

 

How Sugar Affects Your Mind and Mood

 

What is it about these foods? Well, there are actually several different ways they work their magic on your brain:

First, sugar triggers the release of natural opiates within the brain, just as chocolate does, as we saw earlier. Your brain cells have tiny molecular structures on their surface called opiate receptors. When you exercise vigorously, your natural endorphins attach to these receptors, where they act as painkillers and cause the famous “runner’s high.” Endorphins are cousins of morphine and heroin in their chemical structure, but milder in their action, and they activate the dopamine system within the brain’s pleasure center. There is actually a whole family of endorphins and related chemicals. And whether their release is triggered by exercise or by the taste of sugar, the result is a pleasant “feel-good” effect, and whatever physical or psychological troubles might have been bothering you are toned down a bit.

Researchers at the Johns Hopkins University in Baltimore tested sugar’s effects in an unusual way. Their test subjects were babies who were just one to three days old. Needless to say, none of these tiny infants had ever tasted a doughnut, seen a television commercial for sugary cereals, or made a trip to a convenience store. But they had a very noticeable reaction to sugar. The researchers first placed the infants in their bassinets for five minutes, and, naturally, some began to whimper a bit during this time. Then they gave each baby either a tiny amount of sugar in water or else just plain water, dribbling the fluid into the baby’s mouths with a plastic syringe. The effect was almost immediate. Sugar-water stopped them from crying. Water alone did nothing.³

A pacifier can do that, too, but there is a critical difference: If the pacifier is removed, crying can ensue immediately; but sugar’s effect lingers for several minutes, even after the taste is gone. The reason is that sugar causes opiates to be released in the infant’s brain, and these naturally calming compounds stay on after the sugar is gone.

Infants whose mothers were narcotic addicts during pregnancy react very differently. Sugar is useless. They cry whether they get sugar or not. The fact is, these babies were exposed to narcotic opiates in the womb, and their natural opiate circuitry no longer responds normally; they are resistant to its effects.⁴

The opiate effect is probably triggered by the mere taste of sugar, rather than by a rise in the amount of sugar in the bloodstream. A baby’s taste buds are set for the slight sweetness of mother’s milk, and as sugar—which is far sweeter than mother’s milk—touches the tongue, it sets off a chain reaction: The taste buds send impulses through nerves leading to the base of the brain, and from there to the cortex—the outermost layer of the brain. At that point, the baby becomes aware of the sweet taste. And, along the way, nerves stimulate the pleasure center, causing the release of natural opiate compounds that color the experience as an enjoyable one. These opiates also block pain, at least slightly.

Hospitals have taken advantage of sugar’s opiate action. When babies’ blood samples are drawn by a typical heel-stick, a little sugar given in advance has a noticeable calming effect. The same is true during circumcision.

The pronounced attraction that sugar has for children—suckers, gum, sugary drinks, sweetened cereals, and on and on—suddenly starts to make sense. It doesn’t just taste good. It turns on the opiate machinery deep within their brains, which is why it has an essentially magnetic effect on infants. And although, for many of us, sugar’s ability to trigger pleasure starts to wane as we reach adulthood, for others, sugar remains a drug of choice.

Although sugar alone trips the opiate machinery, food manufacturers have found that whipping in a bit of fat accentuates its effects. In fact, many of the foods people call “carbohydrates” actually have at least as much fat as carbohydrate, and this fat-carb mixture may cause an even more pronounced opiate effect, similar to that caused by chocolate. When researcher Adam Drewnowski gave the opiate blocker naloxone to volunteers, as we saw in the Introduction, it not only blocked chocolate cravings, it also cut the craving for potato chips, a classic fat-carb mix.

 

Although sugar alone trips the opiate machinery, food manufacturers have found that whipping in a bit of fat accentuates its effects.

 

That First Bite

 

Sugar causes the release of opiates within the brain. But that opiate response does more than make you feel good. It also has a marked appetite-driving effect. You’ve experienced it: You had a little bit of an appetite before you took your first bite of sugar. Might taste good, you thought. But once it touches your lips, sugar’s opiate effects break through the dam holding back your appetite, and an army of dietitians could not save you from the binge that sweeps you away. Inside your brain, the opiates triggered by the sweet taste are busily resetting all your internal priorities to make you care about one thing and one thing only: eating more of what has just passed your lips.

Some people have a special yen for carbohydrate-rich foods in the wintertime. As the days become shorter, especially at northern latitudes, some people lapse into depression. Many discover that sweet or starchy foods bring them out of it. Far from being a problem, these carbohydrate-rich foods boost a brain chemical called serotonin, which helps regulate moods and sleep. The problems don’t start until bread is topped with butter or other calorie-dense toppings, or when quantity knows no limits. More on this in chapter 9.

There is one additional way that carb-rich foods might get us hooked, and this one relates specifically to bagels, bread, cookies, and cake—anything made of wheat. Researchers have found that the wheat protein, called gluten, breaks apart during the digestive process into compounds that have a variety of mild opiate effects. They can slow down your digestion, just as mild narcotics do, and their effects can be blocked by the same drugs that block the effects of narcotics (e.g., naloxone).^5,6 So far as we know, these wheat-derived opiates work within the intestinal tract and do not seem to pass into the bloodstream. However, some researchers have speculated that druglike compounds released from wheat (or from cheese or other foods, as we will see in chapter 4) may be the trigger that causes psychiatric symptoms in susceptible individuals.⁷ It would not be surprising if researchers were to find that wheat-derived opiates actually can affect the brain, either directly, by passing into the bloodstream, or indirectly, by causing the release of various hormones from the digestive tract. Stay tuned.

 

Is It Good to Break a Sugar Habit?

 

So, are carbohydrates—and sugar, in particular—a biochemical blessing or a calorie-dense curse? Well, that depends. Carbohydrates themselves are not fattening. Despite their repeated condemnation in the popular press, scientific studies clearly show that carbohydrate-rich foods eaten in normal quantities have virtually no effect on body weight. A baked potato has only about 150 calories, a piece of bread about 70. It’s not easy to gain weight with numbers like that. However, there are a few problems you need to look out for.

 

Toppings and Hidden Fat

 

First, what is going on that potato? It might start out with 150 calories, but a tablespoon of butter adds another 100, a dollop of sour cream another 25, and a sprinkle of bacon bits adds 25 more. Pretty soon, the potato is nothing but a vehicle for fatty toppings that have at least as many calories as the potato itself.

Same for bread. Start with a piece of whole wheat bread, with 70 calories. Melt an ounce of American cheese over the top, and you’re suddenly up to 180 calories. Blame the carbs if you want, but it’s the toppings that will really fatten you up.

Far more treacherous are the fats you don’t see. Take popcorn, for example. Air-popped, there are all of 6l calories in a two-cup serving. But cooked by the usual oily method, that innocent popcorn is encumbered with nearly double the calorie load—108, to be exact.

Snack pastries are far worse. There are a 15 grams of fat baked into a pack of Ho-Ho’s or Zingers. And while the label calls them vegetable oils, they are hydrogenated oils, also called trans fats, which are as bad as butter or lard for your arteries and general health.

 

Quantity

 

Now, let’s say you don’t go near the fatty toppings. You could still gain weight from carbs, but you have to work at it. Because carbohydrates are modest in calories, most people fill up before they get very far. And even when you overdo it a bit, many of the calories in carbohydrates are either stored as glycogen—the high-energy molecules your muscles use for power and endurance—or are lost as body heat and are not turned to fat at all. It is no easy biochemical task to convert a piece of bread into human fat, and studies of controlled overfeeding show very little effect from even hefty amounts. Nonetheless, if you take in more calories than you burn, you will gain weight.

 

Sugar

 

If it’s sugar itself you choose, rather than complex carbohydrates like pasta or beans, the calories can come fast and furious, especially as serving sizes have gone out of bounds. And this is where those who criticize carbohydrates make a good point: Sugar is concentrated calories. A typical soda now holds twenty ounces and packs 250 calories of pure sugar. Those calories don’t displace food—they add to whatever else you are eating. In contrast, 250 calories of rice—which is a bit more than a cup, would cause you to compensate by eating less of everything else. So, next time you reach for a soda, remember that you could have a glass of water instead. A cup of rice or three slices of bread have fewer calories than a typical soda.

Despite these potential problems, carbs are not the enemy. Populations whose dietary staples are rich in carbohydrate—rice, noodles, beans, or split peas, for example—tend to be considerably slimmer than those who make meat and cheese their dietary mainstays.

You may also wish to pay attention to how sugar affects your mood. Many people find that, although they crave sugar and it may even have a calming effect, over the long run it makes them irritable and depressed. Some women report that, if they give in to premenstrual sugar cravings they will pay for it with worsening spirits.

You might want to see if this is true for you. If you have moody episodes, take a look at what you were eating during the 48 hours prior, and see if getting off sugar helps restore your moods to a better equilibrium. You may wish to jot down what you’ve eaten each day in a notebook. When you note down sugary foods, you’ll want to include anything with a fair amount of sugar in it—even juices. At the end of each day, rate your overall mood and note any times when your fuse seemed shorter than normal. Separate the premenstrual week from the other three weeks of the month, as food-induced mood changes might be accentuated at that time.

If sweet or starchy snacks have taken over your life, the answer is not to avoid them, but to be selective, keeping an eye on fat content and the glycemic index, a number that shows how quickly carbs release their natural sugars into the bloodstream. We will go into detail on this in chapter 7. Briefly, the glycemic index (GI) of various foods was calculated by feeding them to volunteers and then drawing blood samples at regular intervals. Some foods break apart into sugars very rapidly, others much more slowly, and the faster any given food releases its sugars into the bloodstream, the higher its glycemic index.

For now, all you need to know is that the main high-GI foods are white bread, big baking potatoes, most cold breakfast cereals, and sugar itself. Better choices include pumpernickel and rye bread, which have lower GI values, as do new potatoes, yams, and sweet potatoes. Beans, green leafy vegetables, pasta, and most fruits have very low GI values. Going low-GI lets you eat carb-rich foods without fear.

 

The Sugar Pushers

 

The Sugar Association is an industry group of sixteen sugar companies, one of which I got to know as a child growing up in Fargo, North Dakota. When the wind was right, Crystal Sugar’s sugar beet processing plant sent its distinctive odor over my childhood home.

 

Many people find that, although sugar may have a calming effect, over the long run it makes them irritable and depressed. Some women report that, if they give into premenstrual sugar cravings, they will pay for it with worsening spirits.

 

The Sugar Association is eager to point out that Americans don’t really eat as much sugar as they might think—only about 40 grams (about 10 teaspoons) per day. Not very much, is it? Well, that’s just cane and beet sugar. Plenty more comes in the form of corn syrup—which you’ll find in a great many foods—as well as honey and other sweeteners. Next time you’re in line at a convenience store, pick up any snack pastry. Or look at a typical 20-ounce soda bottle. You’ll find more than 60 grams of sugar lurking inside.

Food companies don’t rely on sugar alone to keep you hooked. In the case of sodas, companies have long added other chemicals to keep you coming back. Coca-Cola’s story began in 1886, when Atlanta pharmacist John Pemberton mixed up a caramel-colored liquid as a cure for headaches. It was sold at Jacobs’ Pharmacy for five cents a glass and was soon advertised as “The Ideal Brain Tonic.” Indeed it was. It was a mixture of cocaine and kola nut extracts. Eventually, the company replaced cocaine with caffeine, but it still qualifies as a “brain tonic,” as any college student who has overindulged the night before will tell you. A 20-ounce bottle of Coke has 58 milligrams of caffeine, and a Diet Coke about 78, slightly less than a typical cup of coffee.

Is the company concerned that kids might get hooked on caffeine? Quite the opposite. Take a look at what the Coca-Cola Company recently posted on its Web site under the category “Myths and Rumors”:

“Caffeine is not addictive. Caffeine has had a long history in the food supply, consumed as long ago as 2700 B.C. Scientific evaluation of caffeine’s physiological effects, in light of the criteria for drug dependence, clearly shows that caffeine is not similar to the use of drugs of abuse or dependence. It is true that some symptoms of withdrawal can be experienced by some people if caffeine consumption is stopped abruptly. When done gradually over a reasonable time period, most people do not even experience these symptoms. More importantly, the amount of caffeine in typical soft drinks is minimal. The amount in most cola beverages is about one third of the caffeine in the same amount of coffee and one half of the amount found in tea.”^*

Caffeine is not addictive? This is what your mother used to call “a lie.” There is no question that caffeine is addictive. And dedicated caffeine users are very familiar with the symptoms, like headaches, that they experience when they stop using it. None of these symptoms is especially serious, of course, and, ounce for ounce, there is indeed less caffeine in Coke than in coffee. But that’s a bit like saying there is less alcohol in wine than in hard liquor. Users of all these products adjust their serving sizes accordingly in order to get the brain effect they seek.

Meanwhile, serving sizes of sugary foods have been carefully and deliberately pushed upward. When I was a child, sodas came in 6-ounce bottles and were only consumed at picnics or other unusual settings. As 12-ounce cans gradually took over, they seemed a bit much to some people, who had trouble finishing them. Many people were frustrated that they could not put stoppers on cans as they could on bottles. Eventually, 12 ounces grew to 16 and then 20. And it is safe to say that not many people save half for the next day.

Down the hatch it goes. Fast-food restaurants and movie theaters serve sodas and virtually no other beverages. This is partly marketing—the supersizing phenomenon that extracts slightly more money from your pocket than smaller servings would—and partly addiction. People acclimating to any addictive substance gradually zero in on their daily dose and then stay there, whether it’s a pack of cigarettes, a beer or two at dinner, or 20 ounces of Dr. Pepper in the morning.

You can break loose, of course. And you’ll very likely feel much better and be glad you left the sugar habit behind. So, even though your infant sweet tooth might make you coo and gurgle a bit when your old friend sugar walks in the room, you will have finally broken the seduction.

 

The Bottom Line

 

• Sugar can be addicting. It triggers the release of opiates in the brain, an effect you can spot even in newborn babies. The primary problem with sugar is that it is concentrated in calories.

 

• When people feel hooked on “carbohydrate,” they are really hooked on foods that release sugars rapidly into the blood (e.g., cookies or potatoes), rather than on carbohydrates that release sugars slowly (e.g., beans, fruit, or pasta). The primary health issue with these foods is not their ability to release sugar, but their fatty toppings or ingredients: butter on toast, sour cream on potatoes, margarine whipped into cookies, etc.

 

• If you’re ready to get that white powder out of your life, the steps in part II will cut your cravings, and the menu and recipe section will give you plenty of healthy choices.

^*http://www2.coca-cola.com/contactus/myths_rumors/ingredients_addictive.html (accessed August 13, 2002)