Medium 9781591200598

Genetically Altered Foods and Your Health

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Roseboro examines how genetic engineering is radically changing our food and explains why organic foods are a practical--and safe--alternative to this risky technology.

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1. Diet and Health: Making Wise Food Choices

ePub

In America, today, poor diets are typically too high in calories and fats, and too low in fruits and vegetablesproblems associated with certain chronic diseases and obesity.

These words, in the introductory remarks of a report issued by the U.S. Department of Agricultures (USDA) Economic Research Service (ERS), depict (long-term) changes in American eating habits, and the consequences resulting from the changes. The report is one in a series of several critical reports issued by ERS on the status of the current American diet, and the implications. Other reports focus on the growing trend of eating away from home, and its impact on the decline of quality in the American diet; the current diet of American children; and an assessment of actual food consumption by Americans, compared with official recommendations.

These reports, examined in toto, confirm and give added weight to concerns already expressed by many nutritionists, dietitians, health practitioners, and public health officials. All groups have reported findings, based on clinical studies, that current American eating habits are poor, and apt to get poorer, due to changes in eating patterns.

 

2. Special Food and Health Concerns throughout Life

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What we now know about human milk is just the tip of the iceberg, remarked Dr. W. Allan Walker, a researcher at Massachusetts General Hospital, in 1979. By the late 1970s, researchers had discovered that human milk is far more complex than formerly appreciated. To date, more than 100 components have been identified in human milk. And surprising findings continue to be made.

For instance, there is growing recognition that, in addition to meeting the human infants specific nutritional needs, human milk provides other subtle but important factors for growth and developmentfactors that could provide for well-being into the adult years.

A Lifetime of Health Benefits. The newborn goes from a sterile womb into a world filled with infectious microorganisms. Immune responses in the infant are, however, incompletely developed. Human milk contains many antibodies, lymphocytes and certain proteins that help protect the newborn from immunologic and infectious complications.

One such antibody, termed IgA, protects against intestinal infections. Infants are unable to produce their own IgA antibodies until months after birth. It is found in abundance in mothers milk. The lymphocyte found in breast milk can prevent necrotizing enterocolitis (see page 39), the prime killer of babies in need of blood transfusions.

 

3. Form and Function: The Body Knows Best

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Anton van Leeuwenhoek, a seventeenth-century Dutch scientist, was astonished by what he saw through a microscope when viewing red corpuscles, body tissues, and various animalculahis term for tiny organisms. By using sophisticated techniques and instruments, the modern counterparts of van Leeuwenhoek can measure various substances at extremely low levels. These substances may be small but are often powerful and may enlarge our understanding of many disciplines, including nutrition, physiology, biochemistry, agriculture, and food science.

Nutrition. A substance in humans, if present in amounts less than 0.01 percent of the body, is considered to be a trace element. Intake of nutrients such as trace minerals and vitamins is vital to our well-being in amounts sometimes as low as micrograms (millionths of grams).

In the case of the trace mineral iodine, the difference between a normal and a severely retarded child may depend on 70 micrograms (mcg) or fewer daily (about two millionths of an ounce). To appreciate how small this amount really is, consider that the same child consumes a billion mcg of food and water daily.

 

4. Basic Foods and Beverages with “New and Improved” Uses

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The conventional wisdom has been that all high-fat foods contribute to cardiovascular risks, promote arteriosclerosis, and contribute to obesity. As with many oversimplifications, this is wrong. All fats are not equal.

Foods rich in monounsaturated fats, such as nuts and olives, and the oils pressed from these foods, defy the dictum. Numerous studies indicate that diets high in monoun-saturated fats actually can lower the risk of cardiovascular diseases, and in some cases, do so even more effectively than the officially recommended low-fat diet.

Some studies have demonstrated that people who eat nuts regularly experience significantly less heart disease and heart fatalities than those who rarely eat this fat-rich food. Nuts eaten slowly release their fat in a healthful way. All nuts have similar oil-encapsulating structures, so their fat-delivery system is similar. Alpha-linoleic acid (an omega-6 essential fatty acid) in nuts is thought to prevent ventricular fibrillation.

Cardiovascular Benefits. Studies conducted jointly in California, Canada, and Italy demonstrated that the substitution of almonds and almond oil for other fats in a diet could lower both total and low-density lipoprotein (LDL) cholesterol (the harmful form of cholesterol). The same research team conducted a five-week period study comparing diets with fat components from olive oil, almonds, and dairy-based fats. During the first week, participants were instructed to select high-fiber, low saturated-fat meals. At the beginning of the second week, each volunteer was assigned to a similar diet, but with different fat components. The diets increased each persons caloric intake from fat to 35 percent in the olive oil and fat groups, and to 39 percent in the nut group. Although these percentages are above the official recommendation of a maximum 30 percent calories from fat, they reflect actual percentages consumed by many Americans (but from fats that are predominantly saturated).

 

5. Sugar: Desired but Undesirable

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Why is sugar so bad when it gives a quick pick-me-up? Energy supplied by refined carbohydrate such as sugar causes the blood sugar in the body to rise quickly. But it falls nearly as fast. Refined carbohydrates, such as sugar, are rapidly digested, and produce a temporary oversupply of sugar in the blood. In turn, the liver and pancreas are stimulated to withdraw this excess, in order to keep the blood sugar level at an equilibrium. This is achieved by converting the excess energy into starch in the liver and storing it in the cells as glycogen, which eventually is converted into fat. The blood sugar level drops after the excess energy is withdrawn, and with this drop, the person feels hunger, fatigue, and a craving for more energy food. It is a vicious cycle.

If no food is eaten, the blood sugar remains at an undesirably low level until it is restored to a normal level, by reconversion of the stored glycogen into blood sugar. But, experiencing hunger, the person may eat before the glycogen is reconverted. Any excess of unused or unconverted glucose is converted into body fat.

 

6. Fats and Oils: What You Should Know

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When the Food and Drug Administration (FDA) considered fortification of foods with folic acid, the agencys then Commissioner, Dr. David A. Kessler, issued a policy statement: Whenever you fortify the entire American food supply with a pharmacologically active ingredient, you need to be sure you get it right and get it right the first time. This policy needs to be applied to other substances considered for approval. Did Kessler get it right the first time with the fat substitute, Olestra (sucrose polyester)?

Olestra Is Pharmacologically Active. Although the public has been led to believe that Olestra is not absorbed, this notion is inaccurate. Dr. George Pauli, from the FDAs Office of Premarket Approval, reported that Olestra is not absorbed in any appreciable amount. Long-term rat studies suggest that some Olestra is absorbed, as reflected by changes found in the animals livers and spleens.

Procter & Gamble (P&G), Olestras manufacturer, reported that the overall sensitivity of the tests was only about 2 to 3 percent of the administered dose. Later studies with rats, guinea pigs, and mini-pigs showed absorption ranging from 0.2 to 1.5 percent. The absorption problem, even at a low rate, may be critical for humans with impaired gastrointestinal tracts, as reflected in the tests with guinea pigs. One group was fed a substance known to cause intestinal damage. After three weeks, these animals with impaired gastrointestinal systems were fed Olestra and developed lesions in their tracts similar to those observed in acute and chronic human gastrointestinal diseases, such as ulcerative colitis and Crohns disease. In feeding tests with mini-pigsanimals whose gastrointestinal tracts are anatomically and physiologically similar to those of humansthe animals absorbed 1.1 percent of the Olestra.

 

7. Dispelling Some Popular Health Myths

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In 1994, the U.S. Department of Agriculture (USDA) proposed to limit sodium in school feeding programs. The Salt Institute, a trade organization, promptly protested. The group contended that removal of high-sodium foods, such as milk and other dairy products, inevitably denies children other important nutrients such as calcium and potassium, present in such foods.

This challenge deserves scrutiny. The USDAs proposal, which forms public policy, is based solidly on scientific evidence. Correct? Incorrect!

Contrary to popular perception, universal sodium restriction is unnecessary, and possibly undesirable. A common notion is that sodium induces hypertension (high blood pressure) and that lowering sodium intake will prevent hypertension. Unfortunately, this notion has no scientific basis. Instead, many recent medical studies have brought into question the effectiveness and even the safety of universal sodium restriction.

There is a relationship between sodium and blood pressure, which is important for about 10 percent of the population, which is sodium-sensitive. For this group, sodium restriction is an important feature, along with other measures, for treatment. However, for about 90 percent of the population, there is no convincing scientific basis for the idea that sodium restriction will prevent hypertension.

 

8. Food Additives and Your Health

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In the early nineteenth century, many food colors were hazardous to health. Pickles were colored, green with copper sulfate; cheeses with red lead and vermillion (red mercuric sulfide); spent tea leaves were colored with copper arsenite, lead chromate, and indigo so that the leaves would appear fresh for resale, and candies for children were colored brightly with lead chromate, red lead, and vermillion. These toxic compounds made many people ill and resulted in deaths.

By the mid-nineteenth century, synthetic industrial dyes were being applied to foods. No regulations existed regarding their purity or uses. Concern for public health led the U.S. Congress to pass the Food and Drug Act of 1906, which restricted use of synthetic colors to those that could be judged safe with foods. The legislation drastically reduced some eighty synthetic colors used with food to only seven. The legislation also established a voluntary certification system, and the synthetic colors became known as certified colors. In 1907, eight additional certified colors were added to the list. By 1938, previously approved certified colors were re-evaluated for safety. Those approved were relisted; some permanently, and others only provisionally. In the intervening years, some have been delisted, that is, banned.

 

9. Avoiding Foodborne Illnesses

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Changes in farm practices, the environment, and lifestyle, as well as in food processing, distribution, and consumption, are all related to increased food-poisoning outbreaks.

One major change has been the increase in available food products. In the 1950s, a typical grocery stocked about 300 items; currently, supermarkets stock some 30,000. To keep all of these foods fresh and wholesome strains the system.

Several decades ago, the classic foodborne outbreak might have been from Salmonella-contaminated potato salad, locally prepared, served at a church picnic, and affecting dozens of people. Today, Salmonella may be present in very low numbers, but in a mass-produced food item distributed to tens of thousands of people far from the processing source. Mass production and international distribution, as well as worldwide travel, create the potential for global foodborne outbreaks.

Of the billions of dollars that Americans spend yearly on food, increasingly more dollars are spent on foods prepared outside the home. To meet consumer demand, the types of foods served in eating establishments have changed. Formerly, many cooked foods such as soups and stews were offered on a limited menu. Currently, many offerings are cold foods, including raw vegetables and fruits, which require extensive handling by preparers, with greater possibilities for transmission of contaminants.

 

10. Contaminants in Our Food

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How safe is our food? And who is monitoring food safety? As federal regulatory agencies devote resources and energy to monitoring the food supply, it is important for consumers to know what programs exist to cope with reported problems. The following discussion is limited to the existing programs and their effectiveness in one area of food safety: the monitoring of pesticide residues in food.

The Food and Drug Administration (FDA) has the greatest responsibility for monitoring pesticides in foods. However, it shares some responsibility with the Environmental Protection Agency (EPA), and the U. S. Department of Agriculture (USDA).

The EPAs Role. The EPA is responsible for registering pesticides and establishing tolerances for any pesticides that may leave residues in food. The tolerance level is the maximum amount of residue that is presumed not to present an unacceptable health risk.

Over the years, the concept of what constitutes an unacceptable risk has widened. Safety tests of pesticides now are required to determine, among other effects, a pesticides potential to cause chronic illness in humans, including reproductive disorders, birth defects, and cancer, as well as environmental damage. In 1972, Congress required the EPA to reregister older pesticides in accordance with current requirements.

 

11. Agricultural Practices That Affect Our Food and Health

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There was a time when our food animals grazed on summer grass and winter hay. Then, it was found that livestock gained weight more readily if fed grains or soybeans. However, by the 1970s, this practice was viewed as costly and wasteful. It was argued that, instead, such valuable food crops should be used to help feed the worlds people. This turnabout stimulated a search for alternative substancesa search that still continues. It has taken us from grass and hay feeding to such nontraditional ingredients in animal feed as sewage sludge and treated manure.

The search for alternative substances in animal feed suited the new conditions that arose from agricultural changes. Formerly, agricultural wastes such as cornstalks, wheat straw, apple pomace, sugarcane bagasse, and citrus rinds were recycled on farms as mulches. Animal manures were composted and spread as fertilizers. The growth of large-scale, specialized commercial farms created problems of costly waste disposal. Also, growing concerns about water pollution and regulations instituted to curb waste disposal acted as an incentive to find solutions. Recycle became a buzzword of the era.

 

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