HEALTH BODY FOOD

Exploring nutrition myths and misinformation.

“IF EVERY ONE of us did everything we’re supposed to do in nutrition, we’d probably add about 11 years to our lives,” says Sanford Miller, director of the Food and Drug Administration’s Bureau of Foods. “But what we’re really talking about today in nutrition is improving the quality of life, not the quantity. People want to know how to maximize their health.”

In some ways the American health picture is looking rosy. According to a recent Surgeon General’s report, life expectancy is rising, the mortality rate from heart disease is falling, and death rates from all cancers except those linked to smoking are going down.

Still, nearly two-thirds of Americans will die from either cancer or a heart attack. Diet seems to be playing a part in these and many other serious diseases. The foods we eat are affecting not only the way we die, but also the way we live – our moods, our aches, our itches, and our pains. Not surprisingly, nutrition is a hot topic.

“People look at Three Mile Island, pollution, Iran, and nuclear bombs and say, ’There’s nothing 1 can do about that, but damn it, 1 sure can control what I put in my mouth,’ ” says Max Milner, head of the American Institute of Nutrition.

Nutrition information is spreading, but much of it seems to be misinformation. “You have to understand,” says Miller, “that this nutrition field is a strange area. Everyone believes that his or her research is accurate and important, but that all his or her colleagues are quacks. The reason is we have lots of hints and some directions – but we don’t know much yet.”

Nutrition is a fairly new science; it was only during the Thirties that vitamins and minerals were discovered and identified. Nutritionists still haven’t isolated all of them. But people prefer easy answers, which aren’t always correct.

“You aren’t what you eat,” says Harold Roth, associate director of digestive diseases and nutrition at the National Institute of Arthritis, Metabolism, and Digestive Diseases. “You aren’t potatoes and hamburgers – it’s more complicated than people think. The problem for medicine is that it came up with some answers [about curing infectious diseases], and now it’s expected to come up with all the answers – and it hasn’t. It’s very hard to do experiments with nutrition -you can’t control people or experiment on them easily.”

For various reasons, doctors have largely ignored nutrition. According to an American Medical Association survey, only 30 of the 126 medical schools in the U.S. require nutrition courses.

Why? Perhaps because there’s not a lot of hard data to examine; nutrition is only in its infancy. Or perhaps it’s because there’s not as much money in preventing disease by establishing healthy eating patterns as there is in applying chemical cures. Whatever the reason, Americans are increasingly eager to take matters into their own hands -and mouths.

Converging factors seem to be helping diets improve. Inflation, for example, has prompted many Americans to eat less red meat and more chicken, a move considered healthy. And people are buying more bread and pasta – low-priced carbohydrates that have been given a bad name, but are actually healthier alternatives to our usual protein and fat.

We seem to be moving in the right dietary direction. But we’ve swallowed a lot of myths along the way, myths that have caused more indigestion than the food itself. Diet isn’t the only thing that will determine health or lack of it, but it’s one of the few things left in life we can control and – once we separate fact from fallacy-enjoy.

Junk food apparently is the cause of much of the aggressive, seemingly uncontrollable behavior associated with the teen years, according to a recent article in American Journal of Clinical Nutrition (AJCN). The average teenager’s diet may lead to severe Vitamin Bi (thiamine) deficiency, which may result in a disorder much like beriberi. As a result, teenagers can undergo personality changes of the nastiest sort.

“It’s been accepted as the normal adolescent personality, this aggression and irritability, this rebelling and having a short fuse,” says Dr. Derrick Lonsdale, a pediatrician and one of the authors of the AJCN article. “But it may be a reflection of this dietary indiscretion.”

Lonsdale says the problem is an old story. “Teenagers often miss breakfast entirely, perhaps eat a school lunch that is often a hamburger and french fries with lashings of catsup. Then they go home and raid the refrigerator for junk food-colas, doughnuts, sweets. By the time they’re through, they may not want the evening meal.”

Lonsdale found that after 20 typical teenagers ate a well-balanced diet, the aggressiveness began to disappear, their personalities softened, and abdominal and chest pains vanished.

“The problem isn’t just a thiamine deficiency,” Lonsdale says. “It’s the whole question of empty calories – high-calorie foods that don’t contain any nutrients.”

Much dispute exists concerning what “junk food” really is. The U.S. Department of Agriculture defines junk food as food that does not provide at least 5 per cent of the recommended daily allowance for protein, Vitamin C, Vitamin A, thiamine, riboflavin, niacin, calcium, or iron per 100-calorie serving. It doesn’t take much to meet this requirement -food companies can even contrive to have candy bars, Twinkies, and cereals that are over 50 per cent sugar escape the “junk” label by fortifying them with vitamins. Still, most sweet and salty snacks fall into this “junk” category.

We shouldn’t jump to conclusions about so-called fast foods. “Fast food isn’t necessarily junk food,” says Howard Appledorf, professor of nutrition at the University of Florida. “There’s this trend toward oversimplification of nutrition, using buzzwords, pretending there are ’good nutrients’- like protein, vitamins, trace minerals, and fiber -and ’bad nutrients’-particularly refined flour, sugar, fats, cholesterol. That’s wrong.

“Look, the ultimate fast food is human mother’s milk,” says Appledorf. “Fast refers to service, not content.”

This will come as a surprise to people who think such food is packed with calories, but Appledorf has concocted a 14-day fast-food diet. Its daily ration of 1200 calories includes breakfast at home, but both lunch and dinner at such establishments as McDonald’s, Pizza Hut, Taco Bell, Burger King, and Arby’s. It allows an average woman to take off one and a half pounds a week -a sensible weight-loss rate.

Appledorf has presented a paper in which he argues that the nutritional content of a Big Mac (or a Whopper), a shake, and fries is closer to federal dietary goals for nutrient balance than the American favorite of steak, baked potato, and salad with rich dressing. Pizza is also said to be not only a nutritionally balanced food, but lower in fats than the steak-potato-salad meal. If true, this is comforting news since Americans eat between one-third and two-fifths of all meals away from home – more than 20 per cent of these at fast-food franchises.

Here is the percentage of calories in carbohydrates, fats, and proteins in a fast-food meal consisting of a Big Mac or Whopper, french fries, and a milkshake:

Burger McDonald’s King

Carbohydrates 49% 45%

Fat 37% 40%

Protein 14% 15%

Total Calories 1104 1180

Here is the breakdown of calories in a meal consisting of steak, potato, and salad (an average from five restaurants):

Carbohydrates 30.8%

Fat 51%

Protein 18.2%

Total Calories 1441

Appledorf says he is not trying to vindicate the $13-billion-a-year fast-food industry, but to clarify a nutritional principle-namely, that no single food is totally healthy or unhealthy and that it is the entire day’s or week’s diet that matters.

Foods don’t always do their dirty work in your stomach. Chinese foods, for example, contain monosodium glutamate, an additive that not only heightens the flavor of food, but dilates blood vessels as well, which can lead to a vascular headache.

Vascular headaches, including migraines, are those throbbing pains that accompany each heartbeat. They occur when blood vessels dilate, allowing the blood flow to increase and swell beyond the capacity of the vessels. The bulging vessels press against nerves and trigger pain impulses.

Hot dogs can also provoke vascular headaches. The sodium nitrite in these and other cured meats is not only suspect as a carcinogen, but it also seems to dilate blood vessels. Hangovers are vascular headaches; alcohol triggers similar vascular action.

Another even more common headache is the tension headache, in which blood vessels are contracted by the repeated tensing of the head and neck muscles. Over-exercising the jaw muscles by eating too much chewy food for too long – especially chewing gum -can cause headaches.

Foods high in the amino acid tyramine can cause both tension and vascular headaches, according to Nelson Hendler, clinical director of the Mensana Pain and Headache Clinic in Baltimore.

Red wines are high in tyramines, which may explain why white wine sales have soared recently. Beer, chocolate, and aged cheeses -especially those with mold, such as blue cheese – are also high in this amino acid. Next in line are dairy products, herring, chopped liver, raisins, fish, nuts, and even some spices. No hard-and-fast rules apply to these foods, Hendler says; each person must experiment with his or her diet to determine which foods cause problems.

Some foods that cause headaches can also sometimes cure them. Caffeine constricts blood vessels, so if you are suffering from a vascular headache, a cup of coffee may ease the pain more effectively than aspirin. However, if you have a tension headache, coffee may only make matters worse. In fact, it was probably drinking too much of it in the first place that triggered or aggravated the tension headache. These headaches are caused by natural elements in our foods, but what about chemical additives and their relationship to cancer?

“Everyone’s worried about chemicals,” says Appledorf. “But the major dangers in foods are of microbial, not chemical, origin.”

Nitrosamine levels are going down in beers and cured meats as a result of public and federal pressure on food processors. But no one can change the fact that they are still present (as sodium nitrate) in celery, lettuce, and radishes. Monosodium glutamate occurs naturally in beets; sodium benzoate is in cranberries; calcium propionate is in cheese; and a natural carcinogen, aflatoxin (produced by a mold), is in many foods.

You can complain about nitrates, dyes, and saccharin, but some scientists insist that salt is the most dangerous additive of all.

There is no doubt that excess salt raises blood pressure in humans-15 to 20 per cent of Americans suffer from high blood pressure (or hypertension), often referred to as the silent killer because it can – without warning-lead to stroke, heart disease, or kidney failure.

From 10 to 30 per cent of Americans have a genetic predisposition to developing hypertension, and blacks are more susceptible than whites. Even those with a genetic predisposition can lower their blood pressure by lowering salt intake.

Is the typical American using too much salt? The Research Council of the National Academy of Sciences (NAS) says yes. The average American eats two to two and a half teaspoons a day – that’s about five grams of sodium. (Table salt or sodium chloride is 40 per cent sodium.) This amount is about 20 times the nutritional requirement for salt, according to NAS, which recommends 3 to 3.5 grams of sodium per day. The Senate Select Committee on Nutrition and Human Needs recommends consuming even less -1.2 grams of sodium.

One serving of many canned soups -including cream of mushroom, chicken and turkey noodle, tomato, and vegetable beef – contains one gram of sodium, nearly one-third of the recommended daily intake; anything seasoned in brine is high in salt. You can eliminate 93 milligrams of sodium just by telling your local fast-food chain to “hold the pickle.” Also high in salt are canned vegetables, snack foods such as pretzels and potato chips, processed cheeses, smoked fish, catsup, mustard, soy sauce, and frozen dinners.

Consumers are advised to look on ingredient labels for any of these other names for salt: sodium chloride, sodium bicarbonate, sodium nitrate, monosodium glutamate, sodium propionate.

Don’t try to eliminate all salt from your diet; you’d die without it. Salt not only keeps body fluids regulated – that includes blood – but aids the transmission of nerve impulses, metabolism of carbohydrates and protein, and heart action.

Under normal circumstances you are at almost no risk of getting too little salt. Even if you threw out your salt shakers and never let preprocessed food pass your lips, you’d still get 20 to 40 per cent of the average American’s intake from natural supplies in food. But in hot weather when you sweat a great deal, or when you have diarrhea, you need to take in more salt than usual. Americans consume 10 per cent fewer calories than they did a decade ago, but are staying just as fat. An increasingly sedentary life seems to be the culprit; instead of exercising, everyone turns to dieting.

Some health experts argue that it is actually healthier in the long run to weigh a few more pounds than most Americans aim for. They say Americans are obsessed with a slender ideal that leaves the body no cushion to fall back on if illness strikes.

Others insist that obesity is America’s leading health problem. The National Institute of Health reports that up to 20 per cent of the population may be overweight to an extent that could impair health and longevity; the problem increases among people over 30. Obesity is linked to breast cancer, diabetes, heart disease, and hypertension.

Nations with a typically high fat intake, such as the U.S. and Canada, have a higher incidence of breast cancer than, say, Japan, where fat intake is low. In Japan, however, fat consumption has doubled in the last decade -and so has the incidence of breast cancer. These links are suggestive, not conclusive.

Even more suggestive were the findings of Dr. Norman Boyd of Toronto’s Princess Margaret Hospital: Women who weighed less than 140 pounds lived longer after contracting breast cancer than did women weighing more than 140.

Being overweight might not only shave years off life expectancy, it might also take dollars off income. A survey by a personnel agency in New York showed that stout executives earned less and advanced slower than their leaner colleagues. Moreover, insurance companies charge people who are more than 20 pounds overweight several dollars extra per $1000 in life-insurance premiums.

Why are Americans fat? Many people blame snacking. But there are as many explanations as there are fat people.

“Snacking isn’t it,” says Appledorf. “Americans are overweight because they do what they were trained to do-eat three well-balanced meals with second helpings. And they’re licking their plates clean for the starving children in Asia. It’s time to question whether the appetizer-entree-dessert approach to meals is valid in view of the sedentary American lifestyle.”

And many Americans are questioning this approach -at least every other month when they’re on a diet. People spend $10 million a year on gadgets and wonder plans. So why don’t diets work?

“We have millions of people in the ’I-lost-800-pounds-in-a-decade’ club. They bounce back and forth, gaining 800 pounds, too. They follow every new miracle diet,” Appledorf says. And none works because people won’t face the boring truth that the only way to lose weight permanently is to count calories in a well-balanced diet.

Here’s a rundown of some of the most popular diets, their claims, and their flaws:

Scarsdale: Though Dr. Herman Tar-nower claimed his blend of foods increases the fat-burning process in the human system, this is not the case. The only advantage to this diet is that it provides a very specific menu, every day, of healthy, low-calorie foods. If you’re too busy to choose your own foods and count up the calories, or if freedom of choice means you’ll run amok, this regimen can be helpful. But there’s no metabolic magic about the specific foods chosen.

Atkins and other single-food-group diets: The Atkins diet -which allows unlimited fats and proteins such as steak, bacon, and butter, but prohibits fruits and starches – claims that digesting protein burns up more calories than digesting carbohydrates, so you can lose weight even if you eat a lot. Not so. The underlying ploy is to focus on one type of food and count on the dieter to get bored with the food and eat less. But eliminating total food groups can lead to vitamin and mineral deficiencies. The AMA has warned that the gobs of fat recommended in this diet could lead to dangerously high levels of blood cholesterol or formation of kidney stones.

Low-carbohydrate diets: These make you lose water quickly over the first week or two. Stepping on the scales seems impressive, but as soon as you resume eating carbohydrates, you’ll regain that weight. The point is to lose fat, not water.

Fabulous fructose diet: Dr. J.T. Cooper claims that if you take fructose supplements (the sugar found naturally in fruits), you won’t experience the sudden rise and fall in glucose levels in the blood that you get from sugar. So you’ll be less hungry, eat less, and lose more. Nutritionists say there is no evidence, however, that fructose curbs appetite. And even though fructose has only half the calories of sugar, avoiding both has the fewest calories of all. Once you peel away the fructose razzamatazz, you’ll find Cooper’s diet a sensible, low-calorie one.

Grapefruit diets: The claim on these is that grapefruit melts cellulite. A pleasant thought, but alas, another myth.

There are dangers with diets. “If you take in less than 1400 calories, it can be very difficult to get the micronutrients – such as zinc, iron, and selenium -that your body needs to do routine repairs and maintenance,” says Appledorf. Calorie intakes below 1000 can also bring on ketosis – the state in which the body burns the fat residues called ketones. This produces a buildup of uric acid in the blood, which can cause kidney problems or gout. It can also lead to a drop in blood présure, which can be a relief for some, a hazard for others. And the mineral loss can cause the hair to stop growing or even fall out.

You’re bound to exercise while dieting, so consider the following:

Muhammad Ali used to eat a thick steak six hours before a fight. O.J. Simpson fasts on the day of a game. Mary Decker, a world-class half-mile runner at age 14, eats a huge plate of spaghetti three hours before a race.

So which path is right? It depends. Getting charged up to win is largely a psychological business, so people must do what they believe in. But there are some nutritional tips to bear in mind.

The notion that athletes in training need a hefty high-protein diet has been discredited. For most sports, a solid, well-balanced diet is all anyone needs -with perhaps a slight increase in volume to provide extra energy. Protein is needed to build muscles, but minimal amounts are sufficient. The size of the muscle depends much more on the demands made on it in exercise than on diet.

High-protein diets can actually increase hazards. They add to the work the liver and kidneys must do to metabolize the protein and eliminate waste products. If all the uric acid wastes are not removed, gout can be triggered. Ketosis and dehydration are also risks. And high-protein intakes are usually accompanied by higher fat intakes. In most sports, athletes perform best when carrying the least possible body fat.

High-carbohydrate diets, on the other hand, have recently been judged beneficial before sports events, especially those of long duration. High-carbohydrate meals, according to Dr. Sharon Vitousek in a recent article in Nutrition Today, are very efficient in that they use less oxygen to produce more energy than protein-or fat. And eating such a diet for several days before a marathon race can increase the glycogen stored in the muscles and thereby increase endurance.

Although extra vitamins are not really necessary, deficiencies in Vitamin C have been found to create problems. Vitamin C is crucial for the synthesis of collagen and tissue repair-more of which goes on in athletes.

It is best not to perform strenuous sports or exercise when food is still in your stomach. It takes about three hours for a meal to be emptied from the stomach (fat empties in five hours, meat in three hours, bread or cereal in two hours).

Athletes should avoid coffee and tea because of their diuretic effect, foods that produce flatulence, and alcohol. But the prohibition on drinking fluids during athletics is considered outdated. It was thought to cause cramps; it is now believed to be more helpful than risky because it regulates body temperature and prevents dehydration and heat exhaustion.

“Americans’ diets are improving,” insists FDA’s Sanford Miller. “We don’t have epidemics of scurvy every winter the way we did up to 1906.” Botulism, salmonella, and other bacterial infections are also rare with today’s improved preservative chemicals and techniques.

We’re being swamped not only with food choices, but also with new nutrition information. But nutritionists are a conservative group and are nervous about recommending what to do with this data. New studies are always suggestive, never conclusive.

How much proof do we need before we can take action? James Lind, a naval surgeon, discovered the cure for scurvy in 1753 -one and a half centuries before vitamins were discovered and before Vitamin C in particular was determined to have a role in the disorder. Untold sailors and sailors’ sons were no doubt grateful that Lind didn’t wait for “proof.”

Still, there is cause for optimism, says Michael Jacobson, head of Science in the Public Interest and usually regarded as one of the voices of doom. “For the first time there’s a national nutritional policy,” he says, referring to the HEW and USDA dietary goals. “In the next decade we should see these new government guidelines put into effect by the food companies. They’re already coming out with low-fat hot dogs and cheeses; they know about salt and additives. There will be significant changes in the American diet,” Jacobson predicts. “I’m hopeful.”

In the meantime, bon appétit.

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