Healthiness Of Foods PDF

2 Healthiness of Foods Garrett is into working out. He is the backup first baseman on his uni- versity baseball team, and he needs to bulk up to get more power in his swing. He works the weight machines every day, but he realizes that exer- cise is only part of a healthy lifestyle and that nutritio...

2 Healthiness of Foods Garrett is into working out. He is the backup first baseman on his uni- versity baseball team, and he needs to bulk up to get more power in his swing. He works the weight machines every day, but he realizes that exer- cise is only part of a healthy lifestyle and that nutrition is the other part. He learns that most foods are unhealthy for one reason or another and that the best way to bulk up is to get rid of carbohydrates and get his energy from protein. He likes fresh, whole foods, particularly meat and dairy products. Jennifer is giving up meat. She is becoming disgusted with the American fast-food culture that features fatty burgers, greasy fries, and sugar-laden drinks. She knows these foods are unhealthy. At first, she just eliminated red meats from her diet. A little later, after hearing about the gross things that happen to chickens on the farm, she now only eats fish. Then, in talking with some of her newfound friends who were also shunning meats, she is thinking about eliminating all dairy products—eggs and anything else that comes from animals. When she stopped hanging out with Garrett because he insisted on keeping his carnivorous habits, she became even more serious. One of the things she likes the best is that this diet is so simple. All she would need to do is to eat anything that is not from animals. She was surprised at the diversity of products available. There are lots of grains, fruits, and vegetables, and they are actually very tasty. At first she was hungry all the time, but after a while the hunger pangs went away. Malik decided to weigh himself on the scale so thoughtfully provided by the cafeteria. He knew he had been gaining weight (or all his jeans were shrinking), but he wasn't sure how much. He looked down and couldn't believe it. He was only halfway through his freshman year, and he had already gained 13 pounds of the dreaded Freshman-Fifteen! It was time for some serious weight loss. What could he do? He'd read that carbohy- drates were the problem and decided to try the latest diet, which replaces all those “nasty" carbohydrates with protein. It was  time to start eating healthy and get away from all that pizza and other junk food served up by the cafeteria. Garrett, Jennifer, and Malik think that their diets are reasonably healthy, but they all have misconceptions. This chapter will explore what healthiness 25 26 Introducing Food Science means. We'll introduce the basic nutrients and describe what we need to consider in designing a healthy diet. 2.1 Looking Back The previous chapter focused on issues concerning the safety of foods. The following key points in that chapter help prepare us for understanding pro- cessed foods: Preservatives are food ingredients that slow spoilage and help pre- vent food-associated illnesses. A processed food should be designed to spoil before it becomes unsafe to make it less likely that someone will eat the unsafe food and become sick. An expiration date represents the food scientist's best guess about how long a food will last before it spoils. Spoilage is not an indicator of a safety risk. Fresh foods are more likely to contain harmful microbes than pro- cessed products.  2.2 Healthy Foods and Unhealthy Foods Many of us are interested in eating healthier, but sometimes it is difficult to know what is healthy and what is not healthy. Foods like carrots, apples, let- tuce, sprouts, whole wheat bread, and yogurt have a healthy image whereas colas, beer, chocolate bars, pizza, hamburgers, fries, and most appetizers in our favorite restaurants don't. It seems that healthy foods are often unappe- tizing or tasteless, but unhealthy foods are temptingly flavorful. Is it possible to eat healthy foods and enjoy them too? When we talk about eating healthy, we are talking about nutrition. Good nutrition involves getting the proper nutrients without consuming too many calories. Obviously, any food that has a good balance of nutrients but can cause food poisoning is not very healthy. Thus, a food must be safe as well as nutritious to be healthy. Food scientists and nutritionists tend to discuss healthy and unhealthy diets rather than healthy and unhealthy foods. Healthy diets require a balance of nutrients and yet allow for a few foods that might not qualify as healthy foods. Unhealthy diets generally do Healthiness of Foods 27 not provide adequate amounts of some nutrients while other nutrients may be present in excess. 2.3 Energy from Foods In a time when it seems that everyone is either overweight, on a low-calorie diet, or both, it is easy to forget the main reason for eating—to get energy. We get energy from food in the form of calories. There are three main sources of calories-carbohydrates, proteins, and fats. Carbohydrates and proteins pro- vide approximately 4 calories of energy per gram (114 calories per ounce). Fats provide approximately 9 calories per gram (255 calories per ounce), more than twice as much as carbohydrates or proteins. That's why we are more likely to lose weight if we cut back on fat instead of proteins or carbohydrates. However, we need a balance in the sources of our calories. Although most of us could stand to cut back on the fat we consume, we do need some fat in our diet. Overall, though, we need to keep in mind that a small amount of fat in our diet (usually no more than 30% of the total calories) is not only healthy but necessary. Despite its deficiencies, fat con- tributes to satiety; that is, it slows down digestive processes and prolongs stomach-emptying time. Meals with a modest amount of fat will need more time to digest, resulting in longer between periods of hunger. Fats are also the vehicle of absorption for vitamins A, D, E, and K (fat-soluble vitamins) as well as other healthy compounds like lycopene. Certain fats have been associated with improved health. Among these fats are omega-3 fatty acids, conjugated linoleic acid, and flaxseed, hemp, and fish oils. We also need protein to perform other functions in addition to provid- ing calories. However, when protein becomes the major source of energy, we may not produce enough glucose in the blood to maintain proper brain functioning. A special class of proteins called enzymes speeds up chemical reactions in the body. These enzymes need special substances (cofactors) to help them perform properly. The enzymes and other molec- ular components in our bodies are constantly under construction. The other main nutritional reason for eating food is to get vitamins and min- erals. Vitamins and minerals are needed to support bodily processes. Essential vitamins and minerals serve as enzyme cofactors or components of these cofactors. A third nutritional component is dietary fiber. Fresh fruits and veg- etables are high in dietary fiber as are products containing whole grains. Dietary fiber is chemically a carbohydrate that comes from the cell walls of plants; much of it is indigestible by the body so it contributes fewer calories than other carbohydrates like sugars and starch. Dietary fiber 28 Introducing Food Science adds bulk to the diet to help keep bowel movements regular. It also helps remove toxins from the intestines and may help in the prevention of many of the diseases associated with overnutrition. Too much dietary fiber, however, can bind vitamins and minerals, thus making a malnour- ished condition worse. Basic nutrition is more simple and straightforward than it is portrayed in the media and in popular books. On the other hand, human physiol- ogy and metabolism (what happens to those nutrients inside our bodies) is more complex than the oversimplified explanations in the same media and books. It is also a good idea to include an exercise plan as part of an overall diet plan. 2.4 Food and Disease One thing many of us are concerned about is how the food we eat will affect our health. Although food-borne diseases can be a concern, when we talk about healthy foods, we are talking about foods that will help us avoid the diseases of civilization (cancer, diabetes, heart disease, and obesity). Hunger, malnutrition, and infection are the major killers in less industrialized socie- ties. More industrialized countries tend to have higher standards of sanita- tion and better healthcare. As a result, the citizens tend to live longer and are Life expectancy Infant mortality Country 2006 2014 2009 Angola 37.6 55.3 180.2 South Africa 42.5 49.6 44.4 Nigeria 47.4 52.6 94.3 Kenya 55.3 63.5 54.7 Bangladesh 62.8 70.6 59.0 Russia 65.9 70.2 10.5 India  68.6 67.8 30.1 Iran 70.6 70.9 35.7 China 72.9 75.2 20.2 Mexico 75.6 75.4 18.4 United States 78.0 79.6 6.2 United Kingdom 78.7 80.4 4.8 France 79.9 81.7 3.3 Canada 80.3 81.7 5.0 Australia Japan 80.6 82.1 4.7 81.4 84.7 2.8 INSERT 2.1 Life expectancy (at birth in years) in 2006 and 2014 and infant mortality rate (infant deaths per 1000 births) in 2009 for selected countries. (Adapted from http://www.infoplease.com as derived from US Census Bureau, International Database.) Healthiness of Foods 29 more likely to become obese and develop cancer, diabetes, or heart disease. During the last 100 years, there have been major increases in life expectancy (see Insert 2.1 for changes in the last decade in selected countries), and qual- ity of life in our aging years is being seen as a more important goal as the aging population grows. Most of the health problems associated with food are caused by either not getting enough food or getting too much. First, our bodies must get enough energy to supply our needs. The unit of energy is the calorie (more appropri- ately, the kilocalorie). Energy provided by food comes from the macronutri- ents (carbohydrates, fats, and proteins), not caffeine or other stimulants. Acute malnutrition resulting in growth failure is attributed to inadequate calories, protein, or both. Overnutrition leads to the development of obesity and associ- ated diseases. Most people get enough protein and calories, but they still can be mal- nourished. Not getting enough of specific vitamins or minerals can result in a deficiency disease. For example, not getting enough vitamin C can result in scurvy, which is characterized by bleeding gums, blotchy bruises, and failure of wounds to heal. Lack of vitamin A can prevent cells from develop- ing properly and lead to night blindness. Anemia can result from not enough iron or a lack of vitamin B12. Osteoporosis is the result of a calcium insuf- ficiency. Such deficiency diseases are worldwide problems. Deficiency dis- eases can be devastating, but the cause, preventive measures, and treatments are clear. Cancer is the most dreaded disease of civilized societies. It has been esti- mated that approximately 20% of the deaths in the United States are attrib- uted to cancer. Cancer is not a single disease; rather, it is a term that groups many similar diseases characterized by abnormal cellular growth and malignancy. The good news is that many cancers are attributed to environ- mental causes and are presumed to be preventable. The bad news is that the causes, treatment, and prevention of cancer are not as simple as for defi- ciency diseases. Cancer is not a deficiency disease of a vitamin or mineral. It is not usually caused by the ingestion of a single carcinogen or prevented by a single food, nutrient, or drug. Although diet plays a role in either increas- ing or decreasing the risks associated with a type of cancer, rarely is it the specific cause. Heart disease is the leading killer in the world. It must be understood that in the classification of causes of death, no one dies of old age. If Garrett lives until the age of 93 when his heart stops beating and nothing else is seriously wrong with him, he will be classified as dying of heart disease. Generally speaking, overconsumption of food, particularly fatty foods, increases the chances of developing heart disease. Smoking and excessive consumption of alcohol are also risk factors for heart disease. Similar risk of developing diabetes. Diabetes is a disease with several levels factors increase the of treat- ment: diet, medication, and insulin injection. Although a diabetic must be very careful with dietary intake, it is not clear that overconsumption of sugar 30 Introducing Food Science in a prediabetic state is the cause of the onset of the disease. As with cancer, the cause, treatment, and prevention of heart disease and diabetes are not as clear as for malnutrition. A word here about cause and effect might be appropriate. An article from the Internet proclaims, "Tea Consumption Doubles the Chance of Conception." The article points out that tea drinkers (presum- ably women) are twice as likely to become pregnant as people who do not drink tea. Now, most of us are sophisticated enough to know that it takes more than drinking tea for a woman to conceive. Is there something in the tea that makes a woman more fertile? Is tea really an aphrodisiac? The lack of a cause-and-effect relationship in this example is clear, but in many things, we see in the media that it is more difficult to separate the cause from the effect. 2.5 Weight Loss without Pain Whether it is fighting the "Freshman Fifteen” or trying to maintain one's appearance for the next social outing, there is a great deal of pressure for weight control and keeping "in shape" on any college campus. Although most of us realize controlling our weight is about diet and exercise, we still hope that there is an easier way to lose weight. Many advertisements for supplements, foods, or weight-loss programs offer remedies without pain. Unfortunately, there is no simple way to lose weight. Fad diets, fat burners, and other miracle weight-loss regimes make empty promises. Counting calories is still the most effective way of monitoring food intake, and knowledge of food composition, keeping a sensible exercise plan, and showing willpower are the three most successful elements of a good weight-loss program. Maintaining a healthy body weight is important in remaining fit and in feeling good about ourselves. We can determine if we have a healthy body weight by locating our body mass index in Insert 2.2. As an athlete, Garrett works out frequently (more than two vigorous sessions of 30 minutes or longer a week) in addition to the time spent in baseball practice and appears to be overweight by the chart, but he realizes that the chart does not allow for extra muscle mass. Jennifer, however, is not heavy  enough. She is probably not eating enough food and could be malnourished. Being underweight may be as much of a health risk as being overweight. Another serious health problem is weight cycling: the repeated loss and regain of body weight. Healthiness of Foods Height Body weight (pounds) Feet Inches 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 5 0 20 21 1 19 20 23 23 25 27 25 29 27 28 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 30 32 34 36 38 40 42 44 45 47 49 51 53 55 57 2 19 22 24 26 27 29 31 33 35 37 38 40 42 44 46 48 50 51 53 55 3 19 21 23 23 27 28 30 32 34 35 37 39 41 43 44 46 48 49 51 53 21 22 22 26 27 29 31 33 34 36 38 40 41 43 45 46 48 50 52 5 20 22 22 25 27 28 30 32 33 35 37 38 40 42 43 45 47 48 50 6 19 21 21 24 26 27 29 31 32 34 36 37 39 41 42 44 45 47 48 7 20 20 24 25 27 28 30 31 33 35 36 38 39 41 42 44 45 47 8 20 20 23 24 26 27 29 30 32 34 35 37 38 40 41 43 44 46 9 19 19 22 24 25 27 28 30 31 33 34 36 37 38 40 41 43 44 10 19 19 22 23 24 26 27 29 30 32 33 35 36 37 39 40 42 43 11 21 22 23 25 27 28 29 31 32 34 35 36 38 39 41 42 6 0 19 22 23 24 26 27 29 30 31 33 34 35 37 38 39 41 123 + 21 22 24 25 26 28 29 30 32 33 34 36 37 38 40 21 22 23 25 26 27 28 30 31 32 33 35 36 37 39 20 21 23 24 25 26 27 29 30 31 32 34 35 36 38 4 19 21 22 23 24 26 27 28 29 30 32 33 34 35 37 Body mass index chart. (From Body Mass Index and Health, Nutrition Insights, vol. 13, No. 2, USDA 2001. www.cnpp.usda.gov/FENR/FENRv13n2 /fenrv13n2p52.pdf.) INSERT 2.2 31 32 Introducing Food Science 2.6 Popular Diets, Food Fads, and Their Consequences The concept of a diverse and balanced diet appears to be giving way to diets tailored to meet unique nutritional needs. Of course, there may few be a individuals with special dietary needs, but, in general, our nutritional requirements tend to be very similar. An overexaggeration of different dietary requirements leads to food fads and can result in malnutrition. The Appalachian Trail Diet (Insert 2.3) is effective, but it is not popu- lar because there are many competing diets that promise quick weight loss with much less exertion. Malik adopted one of the most popular diets by cutting down on carbohydrates and increasing proteins. The idea is that consumption of carbohydrates stimulates insulin production, which leads the body to convert the carbohydrates to stored fat. The diet assumes that consumption of proteins stimulates glucagon production, which leads the body to use proteins and fats for energy. Although this theory sounds good, it ignores the energy needs of the body and the calo- rie levels of food. Most food scientists, nutritionists, and dieticians are skeptical  about the effectiveness of low-carbohydrate/high-protein diets and are concerned that these diets can cause long-term damage to strict followers. Unfortunately, these diets are very popular with many physi- cians, who tend to have limited training in nutrition but serve at the front lines of dietary guidance. In many parts of the world, the average person takes in 70% or more of their calories from carbohydrates, whereas the average American tends to take in less than 50% of daily calories from carbohydrates. Nevertheless, Americans are more likely to be overweight than people from other coun- tries. If low-carbohydrate diets can trick people into losing weight, why are they considered harmful? When we don't consume enough carbohydrates and consume too much protein, our bodies begin to use the protein as fuel and not as material to make new proteins. Too much protein in our diet also leads to excretion of excessive urea in urine, which can lead to severe kidney damage. High- protein diets can also lead to a loss of calcium, and they also frequently contain high levels of fat. In addition, the body cannot store protein; thus, it converts the excess protein to fat and then stores it. Furthermore, low- carbohydrate diets result in an imbalanced state called ketosis. In keto- sis, the body cannot maintain enough blood sugar to meet the needs of the brain, with extended periods of ketosis possibly resulting in brain damage. Eating a balanced diet does help us make the most of what we have. Claims that food or supplements can make us smarter or help us concen- trate are exaggerated. Stimulants such as caffeine can help us stay awake and increase our attention level; however, too much caffeine can make us irritable and lead to anxiety attacks. Healthiness of Foods Toll of the trail How do eight weeks of hiking affect the human body? Prior to setting out on the Appalachian Trail, reporter Scott Huler, 35, dropped by the Raleigh Athletic Club to have some vital statistics recorded. Then, within a week after completing his 410-mile stint, Huler, who is 6'3", was re-examined. Some key findings: Before After Stat Chest (3/20) (5/10) 36 342 Arm (flexed)  12 Waist 342 30 Hips 374 361/4" Thigh (flexed) 22/4 21 Calf 15 14/ Weight 172 lbs. 162 lbs. Blood pressure 106/76 110/72 (resting) Heart rate (resting) 62 66 (in beats per minute) Body-fat analysis 8.6% 6.2% Bench press (max.) 160 lbs. 175 lbs. 155 lbs. Leg extension (max) 135 lbs. An average day of food consumption for Trail diet a hiker looks something like this: Food BREAKFAST Oatmeal 160 16 4 33 Tangerine 65 91 1 Pop-Tart 210 70 3 34 LUNCH Cheese  300 210 Bread 140 Peanut butter 380 260 Jelly 50 Dried-meat stick 280 110 24 0.5 32 12 SNACKS Snickers bars (2) 560 240 72 28 Gorp 1,240 320 30 174 49 DINNER Freese-dried 500 160 Lipton dinner Total 3,885 1,291 116 457 162.5 *Includes raisins, peanuts, M&Ms and granola The US Department of Health and Human Services recommends a normal daily diet of about 2,000 calories. A person Huler's size, carrying his backpack, walking 3 mph, would burn about 354 calories per hour. By comparison, he might expect to burn 432 calories per hour doing calisthenics or 630 calories per hour swimming. 33 INSERT 2.3 Appalachian trail diet. (From Huler, S., “Appalachian Adventures," Charlotte News and Observer, 1995. With permission.) 34 Introducing Food Science Academy of Nutrition and Dietetics, http://www.eatright.org Center for Nutrition Policy and Promotion, http://www.cnpp.usda.gov FITDAY, http://www.fitday.com Food Insight, http://www.foodinsight.com Nutrition.gov, http://www.nutrition.gov Sports, Cardiovascular and Wellness Nutrition, http://www.scandpg.org/sports-nutrition/ USDA, ChooseMyPlate.gov, http://www.ChooseMyPlate.gov Weight Watchers, http://www.weightwatchers.com INSERT 2.4 Some websites to consult to get more information on nutritional quality of foods and develop- ing reasonable diet plans. Lack of enough calories interferes with our ability to stay alert and atten- tive. On the other hand, too many calories can lead to sleepiness and lazi- ness. Inadequate consumption of vitamins and minerals can also affect our ability to concentrate. There is some evidence that certain foods (or their components) can affect our mood, but the linkage has not been clearly estab- lished. There are few if any magical foods, but a balanced diet contributes to health and well-being, whereas a poor diet can lead to laziness, inattentive- ness, and a bad attitude. The sad part about many food fads is that people who intend to eat healthy do not know the nutritional benefits or detriments of a particular food, supplement, ingredient, or component in the context of an overall diet. Thus, by trying to improve their health, they may actually be harm- ing it. There is much good information about health in the news media, but there is also much misinformation. For some useful websites on nutrition, see Insert 2.4. 2.7 Fake Fats If low-carbohydrate/high-protein diets don't work, then should we lower fat consumption? Since an ounce of fat contains twice the calories as an ounce of protein or carbohydrate, we can cut back our calorie consumption twice as fast if we cut out fats. There are many ways we can reduce calories in our diet. One way is to just do without them. Another way to avoid fats is to eat foods typically low in fats. The main problem with low-fat diets, however, is that most people get easily discouraged and give up because they miss the flavor that fat provides and end up cheating on their diet. The technological solutions designed by food scientists are low-fat ver- sions of typically fatty foods, which would allow Malik to enjoy his favorite foods without consuming large amounts of fat. It is not as simple as just Healthiness of Foods 35 removing the fat, however. For example, removing all the fat and sugar in a large cup of frozen yogurt results in a very small cup of yogurt that is not nearly as appetizing and flavorful. Still, there are several ways to lower the fat content in foods. One way is to replace the fat with carbohydrates, pro- teins, or a combination of both. Unfortunately, this approach does not always result in caloric reduction. Another way of lowering the fat is by replacing it with something that adds bulk to the product but does not provide calories. However, there is a price to pay for consuming too much of these delicious treats-bloating and digestive distress. Reducing fat consumption can also be achieved by using the so-called fake fats like Olestra®. These fake fats have all the taste sensations of true fats in the mouth, but the body is not able to absorb them; thus, they have no calories. Olestra is in many products, but probably the product that most people are familiar with is fat-free potato chips. Unfortunately, Olestra interferes with the body's ability to use vitamins A and D properly. This problem is remedied by replacing these vitamins. Another problem with Olestra is that its lubricating properties in the mouth are duplicated in the lower intestines, resulting in some rather loose stools. This problem is not usually a major one for people who refrain from eating large amounts at a single sitting. Although fat reduction can be an important part of a disciplined weight- loss plan, there are some typical mistakes dieters make with foods. First, the more they lower fats in their diet, the harder they find it to stick with the diet because fats contribute to the enjoyment of foods. Generally, a reduced-fat food is more likely to satisfy than one that is fat-free. Regardless of how fats are reduced in the diet, weight loss will not occur unless there is a reduction in calories. That is, if we cut half the fat, yet eat twice as much, we will not lose weight. 2.8 Dietary Supplements, Nutraceuticals, and Functional Foods Dietary supplements are substances that are taken to supply a need or rein- force one's diet. Until recently, the term was used to describe pills that were consumed to make up for an essential nutrient that was not supplied by the diet. In the past, parents provided their children with vitamins and minerals in a single pill a day (sometimes in the form of a favorite cartoon character) to make sure they were not deficient in any essential nutrients. Now, we can supplement the nutritional quality of our diet with protein powders, medici- nal herbs, supernutritious chocolate bars, and many other foods that make nutritional claims. Most dieticians prefer that we obtain our vitamins and minerals from whole foods. Sometimes, however, supplements of specific nutrients are 36 Introducing Food Science needed in special circumstances. For example, women of childbearing age typically need additional iron and folic acid, vegetarians need more iron and vitamin B12, and lactose-intolerant individuals need additional calcium. Dietary supplements have now gone beyond the supplying of essential nutri- ents. We are now consuming garlic for infections and prevention of athero- sclerosis, cranberries to maintain a healthy urinary tract, echinacea for the treatment of sore throats and colds, and St. John's wort for depression. We are beginning to think that we can treat our symptoms at home for most diseases without the need of a physician. Nutraceuticals are foods specifically designed to act as drugs. Nutra- ceuticals are the food industry's answer to the health-food market. Many of these ingredients are added to improve mood. Although there appears to be a relationship between foods and mood, the linkage has not been clearly established. With the potential profitability of nutraceuticals, food compa- nies have rushed in to gain their share of the market. One problem that food scientists face in designing nutraceuticals is producing a truly healthy prod- uct that also has good sensory quality because  many of the ingredients used to formulate a product have a nasty flavor. Food scientists need to find ways to build in flavor without losing the nutritional value or health benefits of the product. Functional foods are marketed to perform a specific function. Two of the hottest trends in food products today are nutrition and convenience. Vitamin- and mineral-filled chocolate bars and drinks provide quick, easy nutrition with the extra fat and sugar providing a pleasant way to get all the nutrients one needs. Likewise, sugared and fortified breakfast cereals per- form a similar function. Sports drinks supply vitamins and minerals, as well as electrolytes to replenish the ones lost in sweat during a workout. Calcium- fortified orange juice provides an alternative to dairy products for consum- ers who dislike or have sensitivities to milk. With the discovery of additional benefits of certain components, some traditional foods are now being pro- moted as functional foods. For example, ketchup is high in lycopene, which is a powerful antioxidant, and mustard is now being touted as being health- ful because of the presence of antimicrobial compounds and antioxidants. With all this information available, how is the consumer supposed to cope with it when even professionals have trouble sorting through it all? There are some guidelines we should consider next time we buy a supplement, nutra- ceutical, or functional food: It is a fallacy that if a little is good, a lot is better (it might even be toxic—just like drugs, leading to an overdose). Many of these substances have not been thoroughly studied, and when studied have generally been tested in isolation and not in the presence of the wide variety of substances that make up a typical diet. Healthiness of Foods 37 A substance may be present but not at a high enough level to be effective (much more may be needed to cure depression, acne, or warts than is available in that herbal tea). An effectively high dose may be doing other damage (some of these supplements cause serious interactions with prescription drugs). There may be other components present that could have adverse effects when consumed at too high a level. As the medical and nutritional sciences advance, we will find substances and combinations of substances that are truly beneficial to health. Presently, however, there are more products available that consumers trust and are willing to buy than there are products with proven health benefits. It remains to be seen if the growth of dietary supplements and functional foods is a fad, a fundamental change, or a springboard for new products that will be permanently incorporated into our diets. It is hard to believe that the original Kellogg's and Post breakfast cereals that are so much a part of our culture today were part of the health-food craze that affected Americans of the late 1800s. 2.9 Enhancing Athletic Performance There is one group of consumers who is particularly interested in nutrition and in dietary supplements-athletes. They are looking for performance enhancement through dietary supplements. The most important nutritional need of an athlete is additional calories. Insufficient calories to replace the ones burned off during exertion and exercise will result in weight loss, and excessive weight loss results in loss of strength. The increased calories of an athlete's diet require increased levels of vitamins, but there is little informa- tion to support megadosing with vitamins. Women athletes generally can benefit from extra calcium and iron. It appears that athletes have a greater need for dietary iron than nonathletes. Increased protein consumption may lead to increases in muscle nitro- gen balance in active athletes. Protein supplements are available as whole proteins or amino acids in the form of pills, powders, and potions. Protein powders are likely to contain nonfat dried milk, soy products, and other non- animal sources. Consumption of large amounts of animal proteins, like a big juicy steak, is likely to add excess fat and cholesterol to the diet. The build- ing blocks of proteins are amino acids. Our digestive system breaks down the proteins we consume into amino acids. The consequences of consuming large doses of amino acids have not been widely studied, although some, 38 Introducing Food Science like tryptophan, can have toxic impurities that can lead to illness or death. Consumption of individual amino acids is not recommended, as they may lead to metabolic imbalances. Branched-chain amino acids are particularly popular, as they are thought to be more likely to serve as energy sources and to enhance serotonin production. Serotonin may enhance performance and raise the threshold for pain, but the short-term gain could have undesirable long-term consequences. Optimal diets for athletes in training are 60%-70% calories from car- bohydrates, 25%-30% calories from fat, and 10%-15% calories from pro- tein-not the low-carbohydrate, high-protein diets many are trying. Whether we are participating in intercollegiate athletics or just working out on our own, our diet should meet both our long-term and short-term health needs. There are many good books on sports nutrition that are based on solid nutrition science. One is listed in the Further Reading section of this chapter. There are many not-so-good books, articles, and individuals who have strange ideas about sports, training, exercise, and nutrition. We shouldn't let them experiment on us with their untested ideas, as we could be suffering the consequences many years after we are finished with competitive sports. 2.10 Six Glasses a Day Water is the major component of most foods. Next to oxygen, it is the most important nutrient for our body. We can only live a few minutes in the absence of oxygen and a few days without water. It is recommended that we drink one and one-half quarts (approximately six glasses) of water per day. The idea that we can only get water from the bottle or the tap is misguided, though; we can obtain sufficient water from foods and beverages; however, we must not think we are getting sufficient water when we drink caffeinated or alcoholic beverages. Caffeine and alcohol are diuretic, which means they increase the frequency of urination. Thus, some of the water goes down the toilet rather than meet- ing our daily needs. That is why our trips down the hall or stops at the rest areas are more frequent when we drink too much coffee, cola, sweet tea, beer, or similar refreshments. Another problem with consuming too many sugared or alcoholic beverages is that we may be adding excess calories and thus add- ing to a potential weight problem. In dry climates, we need to consume more water because we lose more of it through the pores  in the skin than in moist climates. Although water collects on our skin as beads of sweat in humid cli- mates, it evaporates immediately into the dry air in dry climates. Electrolyte (sodium and potassium) balance is essential in maintaining proper water bal- ance in our tissues. An extreme case is where individuals have consumed too Healthiness of Foods 39 much water (water intoxication or overhydration), which can lead to death owing to low levels of sodium in the blood. 2.11 Fasting People of many religious faiths practice fasting as a way to purify the mind and the body. Fasts usually involve the elimination, for a period, of all solid foods. Juice fasts permit the consumption of nutritious beverages, but strict fasts do not even permit the consumption of water. Ramadan is a month of strict fasting from sunup to sundown practiced by Muslims. Every Jewish person over 13 is expected to fast for 24 hours at Yom Kippur. Drinking of water is permitted. Fasting is an integral part of the Hindu religion. It was an important part of the early Christian church, but fasting is not as widely practiced by Christians today. Even for a short time, fasting is an effective expression of self-sacrifice. Spiritualists who fast recommend starting with small fasts before progressing to extended ones. Fasting, combined with meditation, tends to help us focus on the things that are really important in life, but it can have nutritional conse- quences. Fasting is self-starvation and can result in severe nutritional deficien- cies. When we consume more energy than we burn, we store excess calories as glycogen (animal and human reserve of glucose) and fat. During a fast, the body breaks down glycogen first, followed by fat. As stated previously, the brain needs glucose to function properly. When blood glucose is low, it sends signals out to break down fat and protein. In an extended fast, proteins are broken down, producing ketone bodies leading to ketosis. During a total fast, up to a half-pound of fat can be burned at the potential cost of loss of brain function as the ketone bodies are not an adequate substitute for glucose.  2.12 Eating Disorders Eating disorders develop when peer pressure clashes with biological needs. The most common eating disorder is anorexia. It involves a self-induced fast to lose weight. Advanced stages of anorexia can interfere with normal sleep, induce depression, and lead to malnutrition. In the second stage of anorexia, anorexics become desensitized to hunger pangs and develop an aversion for most foods, eating just enough to survive but not enough to thrive. The body shuts down vital processes to conserve energy. The final stage of anorexia results in wasting, withering, and death, similar to starvation associated with famines. 40 Introducing Food Science A related disorder, bulimia, results in anorexia through self-induced vom- iting or excessive use of laxatives, enemas, or diuretics. Since the food is not in the body long enough for most of the nutrients to be absorbed, weight loss and other symptoms of anorexia result. Binge eating is a frequent response to stress (exams, grades, dysfunc- tional personal relationships, and peer pressure), resulting in weight gain. Binge-and-starve diets result in nutritional imbalances and interfere with the body's normal metabolic processes. People with this disorder are par- ticularly susceptible to zinc deficiencies. Studies have shown that women, particularly those of college age, tend to be more susceptible to eating disorders than men owing to hormonal secretions and greater social pressure to be thin. It is very important to catch an eating disorder before it gets out of hand. Treatment is painful and serious digestive problems, such as spastic colon, can persist after a normal diet has been resumed. Most college campus health centers have Signs and symptoms of anorexia nervosa Weight loss leading to a body weight of 85 percent of what's considered acceptable Intense fear of being "fat" or gaining weight Frequent weighing Develops ritualistic eating habits, such as cutting food into tiny pieces, eating alone, and dragging out  meals Loss of menstrual period Excessive exercise Increased sensitivity to cold Refuses to admit eating patterns are abnormal Withdraws socially Signs and symptoms of bulimia Preoccupation with food, weight, and appearance Eats large volumes of food and then "gets rid" of it by vomiting, fasting, exercising, or taking laxatives Experiences mood swings and depression Dental problems Stomach and digestive problems-such as bloating, constipation, diarrhea Scratched or scarred knuckles from scraping against teeth to induce vomiting Irritation of the esophagus and throat Realization that eating pattern is abnormal Irregular menstrual periods How to help a friend with an eating disorder Choose a time and place to talk away from distractions and other interruptions. Don't be judgmental. INSERT 2.5 Be a good listener, but don't promise to keep serious information confidential. Don't assume the role of a therapist or nutritionist. Don't oversimplify the problem by saying, “All you have to do is eat.” Don't engage in a battle, but don't ignore the problem. Signs and symptoms of anorexia and bulimia and how to help. (Excerpted in part from Litt, A.S., The College Student's Guide to Eating Well on Campus, Revised and Expanded Edition, Tulip Hill Press, Bethesda, MD, 2005, Chapter 6. With permission.) Healthiness of Foods 41 programs that will provide counseling. For more insight into eating dis- orders, see Insert 2.5. 2.13 Natural, Organic, and Whole Foods Many consumers are concerned about the foods produced by modern food technology. They long to return to simpler, more "pure" foods. These con- sumers reject many of the commercially packaged foods, believing that nat- ural, organic, or whole foods provide more nutritious and safe alternatives. However, food scientists do not believe such alternatives are necessarily more nutritious or safe. Although natural, organic, and whole foods are sim- ilar, they also have distinct differences. Sometimes, it is difficult to distin- guish the difference between these foods. To confuse matters further, some consumers use different definitions to identify certain foods. Classifying the foods in Insert 2.6 is not as simple as it first seems. Natural foods can be found in nature, unlike colas, potato chips, snack cakes, breakfast beverages, nutritional bars, and frozen entrees. What “natu- ral" means, however, is not always clear and, in fact, there are no standards or regulations regarding the production of "natural" products, especially if they do not contain meats or eggs. Few would argue that fresh garden veg- etables, meat from animals hunted in the wild, or mushrooms and herbs gathered in the woods would qualify as natural foods. Most, but not all, con- sumers would consider fresh vegetables grown in greenhouses, beef steaks from a supermarket, or dried spices also to be natural. Items such as canned corn, breads, pastas, and juices are more difficult to classify. Are natural products more nutritious or safer than "unnatural" ones? Food scientists believe that we need more information to make that determination. A freshly picked ear of corn is more nutritious if it is cooked properly shortly after harvest than if it is canned. Overcooking the ear of corn, however, can be just as damaging to the nutrients as the canning process. If we quickly blanch and freeze the ear of corn, it will retain its nutrients much better than if it is stored for several days in the refrigerator. Most food scientists would take their chances with a fresh beef steak from the supermarket that has been inspected by the United States Department of Agriculture (USDA) over a fresh venison steak from a weekend hunter who has slaughtered and cut up the deer in a neighborhood deer cooler. According to the USDA, “Organic is a labeling term that indicates that the food or other agricultural product has been produced through approved methods. These methods integrate cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity. Synthetic  fertilizers, sewage sludge, irradiation, and genetic engineering may not be used." Organic food production attempts Ligh Silk SOYMIL K M BEEF Silk and Silk Live! are registered trademarks of WhiteWave Foods Company; use of photo is authorized Courtesy of Melissa's Organics, Melissa's World Variety Produce, http://www.melissas.com 10 Earthbound Farm. ORGANIC E Courtesy of The Beef Checkoff Peanut Patc GREEN BOILED PEANUTS 42 INSERT 2.6 SEASO NED Tofu Chines e Spice Silken FIRM Court esy of Morin ga Nutriti onal Foods, Inc., http://w ww.mo rinu.co m arthbound 104 Mini Pecked Carrot s Courtesy of Earthbound Farm, http://www.ebfarm.com 60 Courtesy of McCall Farms and Margaret Holmes Foods, http://www.margaretholmes.com Which of the following products are natural, organic, processed, or whole foods? Natural: fruit, steak, and carrots; organic: fruit and carrots; pro- cessed: soymilk, tofu, and peanuts; whole: fruit, corn, carrots, and steak. Based on the information provided and the definitions of the terms. Introducing Food Science Healthiness of Foods  43 to minimize inputs of fossil fuels and synthetic chemicals. Animal manure and composted plant materials serve as fertilizers for organic crops. Organic products have a marketing advantage, but they tend to cost more and have a shorter shelf life than their conventional counterparts. As described above, a freshly harvested plant part is likely to be more nutritious than one that has been shipped and stored for a longer period. However, there is little, if any, scientific evidence to support the claim that organic foods are more nutritious and safer than conventional products. For example, the use of animal manure as a fertilizer certainly does not make a crop safer, particularly a root crop like potatoes or carrots. The term organic is also used to describe meat products that come from animals that have not been treated with antibiotics or synthetic growth hor- mones and have consumed feeds that were not treated with pesticides. There are legitimate concerns about the overuse of antibiotics because it has been shown that antibiotic overuse can produce drug-resistant strains of bacteria, which threaten human health. Meats that claim to be "hormone-free" are misleading because hormones are natural components of any plant or ani- mal. Thus, the only truly "hormone-free" foods are distinctly “unnatural.” Whole foods are those foods that are readily identifiable by their original components. Milk, fresh or processed fruits and vegetables, as well as whole or ground meats would be considered whole foods. Generally speaking, whole foods have more nutrients with less sugar and fat than many snack foods. There are exceptions, such as ripe bananas, which have very high levels of sugar; avocados (or guacamole); and butter, which are very high in fat. Also, fortified breakfast cereals could hardly be considered whole foods, but they contain an extensive list of vitamins and minerals. Food scientists consider synthetic nutri- ents to be just as effective as natural ones. Once again, a name such as "whole food" does not guarantee better nutrition. We need more information about the product before we can determine how nutritious or how safe it is. 2.14 Reading the Label Nutrition labels can help us with the nutritional quality of our diets. Fresh fruits, vegetables, and meats do not have nutrition labels, but there are many resources we  can refer to for these values. The Nutrition Facts part of the label indicates the serving size, how many servings per container, calories per serving, and the fat calories per serving in the left column. Then there is a chart that provides the amount per serving of the macronutrients (total fat, total carbohydrate, and protein). Fat is further broken down into saturated fat, polyunsaturated fat, monounsaturated fat, and trans fats. Although a contro- versial issue in nutrition, it is recommended that we limit our intake of trans fats. At best, they count as saturated fatty acids; at worst, they could be toxic. 44 Introducing Food Science Product A Nutrition Facts Serving Size (21g) Servings Per Container Amount Per Serving Product B Nutrition Facts Serving Size (236g) Servings Per Container Amount Per Serving Product C Nutrition Facts Serving Size (213g) Servings Per Container Amount Per Serving Calories from Fat 50 Calories 70 Calories from Fat 0 Calories 130 Calories from Fat 45 Calories 210 % Daily Value* % Daily Value* % Daily Value* Total Fat 0g 0% Total Fat 5g 8% Total Fat 6g 9% Saturated Fat g Saturated Fat 3g 15% Saturated Fat 2g 10% Trans Fat g Trans Fat g Trans Fat g Cholesterol Omg 0% Cholesterol 20mg 7% Cholesterol 20mg 7%  Sodium 170mg 7% Sodium 130mg 5% Sodium 840mg 35% Total Carbohydrate 15g 5% Total Carbohydrate 13g 4% Total Carbohydrate 31g 10% Dietary Fiber 1g 4% Dietary Fiber g Dietary Fiber 2g 8% Sugars 2g Sugars 12g Protein 4g Protein 8g Sugars 14g Protein 9g Vitamin A 10% Vitamin C 15% Vitamin A 15% Vitamin C 4% Vitamin A 6% Vitamin C 6% Iron 30% Calcium 30% Calcium 6% Iron 8% *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: Calories 2,000 2,500 Total Fat Less Than 65g 80g Total Fat Calories 2,000 Less Than 65g 2,500 80g Total Fat Calories Less Than 65g 2,000 2,500 80g Saturated Fat Less Than Cholesterol Less Than Sodium Less Than Total Carbohydrate 20g 300mg 2,400mg 300g 25g 300 mg Saturated Fat Cholesterol 2,400mg Sodium Less Than 20g Less Than 300mg Less Than 25g Saturated Fat Less Than 20g 25g 300 mg Cholesterol Less Than 300mg 375g Total Carbohydrate 2,400my 300g 2,400mу Sodium Less Than 2,400mg  300 mg 2,400mу 375g Dietary Fiber 25g 30g Dietary Fiber 25g 30g Total Carbohydrate Dietary Fiber 300g 375g 25g 30g ⚫ Protein 4 Calories per gram: Fat 9 Carbohydrate 4 Calories per gram: Calories per gram: Fat 9 Carbohydrate 4 Protein 4 Fat 9 Carbohydrate 4 Protein 4 Product D Nutrition Facts Serving Size (121g) Servings Per Container Amount Per Serving Product E Nutrition Facts Serving Size (302g) Servings Per Container Amount Per Serving Calories 200 Product F Nutrition Facts Serving Size (35g) Servings Per Container Amount Per Serving Calories 20 Calories from Fat Calories from Fat 90 Calories 210 Calories from Fat 190 % Daily Value* % Daily Value* % Daily Value* Total Fat g Saturated Fat g Trans Fat g Total Fat 10g Saturated Fat 2g Trans Fat g 15% Total Fat 21g 32% 10% Saturated Fat 3g 15% Trans Fat 0g Cholesterol mg Cholesterol 40mg 13% Cholesterol Omg 0% Sodium 390mg 16% Sodium 110mg 5%  Sodium 160mg 7% Total Carbohydrate 4g 1% Total Carbohydrate 7g 2% Total Carbohydrate 4g 1% Dietary Fiber 2g 8% Dietary Fiber 3g 12% Dietary Fiber 0g 0% Sugars 2g Sugars g Sugars 4g Protein 1g Protein 21g Protein Og Vitamin A 6% Calcium 2% Vitamin C 4% Vitamin A 0% Vitamin C 0% Iron 4% *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: Calories 2,000 2,500 Total Fat Saturated Fat Cholesterol Sodium Total Carbohydrate Dietary Fiber Calories per gram: Less Than 65g Less Than 20g Less Than 300mg Less Than 2,400mg 300g 25g 80g 25g 300 mg 2,400mg Total Fat Saturated Fat Cholesterol 375g 30g Sodium Total Carbohydrate Dietary Fiber Calories 2,000 Less Than 65g Less Than 20g Less Than 300mg 300 mg Less Than 2,400mg 2,400mg 300g 375g 25g 30g 2,500 Calories 2,000 2,500 80g 25g Total Fat Saturated Fat Cholesterol Less Than 65g 80g Sodium Total Carbohydrate Less Than 20g Less Than Less Than 25g Dietary Fiber 300mg 2,400mg 300g 25g 300 mg 2,400mg 375g 30g  Calories per gram: Calories per gram: Fat 9 Carbohydrate 4 Protein 4 Fat 9 Carbohydrate 4 ⚫ Protein 4 Fat 9 Carbohydrate 4 Protein 4 INSERT 2.7 Nutritional labels for products A through F as described in more detail in Insert 2.8. The two categories listed under carbohydrates are dietary fiber and sugars. The amount per serving of sodium must also be listed. In addition, the percent daily value is included for all the nutrients except sugar and sodium. The percent daily values for vitamin A, vitamin C, calcium, and iron are also given as well as for the micronutrients that contribute significantly to our diet from this product. Healthiness of Foods 45 It is important to keep in mind that all values are stated in terms of the amount per serving. A bag of chocolate chip cookies may contain 75 cook- ies, but the serving size may be only 5 cookies. The label indicates that the product provides 4% of the daily value of iron, 11% of the daily value of fat, and 150 calories. Five cookies can be a nice snack, but, if we eat the whole bag, we will get 60% of our iron, 165% of our fat, and 2250 calories! We probably should look elsewhere to get our iron. Malik designed a Look at the Nutrition Facts statements of the six items in Insert 2.7. From them, simple meal plan for a day. He had a big bowl of breakfast cereal containing three servings and a single serving of 2% milk. He drank some water but was hungry by midmorning. He resisted the temp- tation to hit the vending machine. Lunch was rushed between classes, so he heated the lasagna entree for 90 seconds in the microwave and chased it with the entire can of green beans, which is two servings. He, of course, had another two glasses of water with the lasagna and green beans. In the after- noon, he ignored his hunger pangs and looked forward to his evening meal. For supper, he went to his favorite fast-food restaurant to consume a healthy grilled chicken salad topped with basil vinaigrette dressing along with more water. They gave him two packs (one serving each) of the salad dressing, but he only used one. There are other significant items on a food label. One is the ingredient statement as shown in Insert 2.8. The ingredients are listed by quantity- from the most to the least. The milk and canned beans are very simple pro- cessed products, whereas the cereal, lasagna, and salad dressing are complex  Item A-Breakfast cereal Rice, wheat gluten, sugar, defatted wheat germ, salt, high fructose corn syrup, dried whey, malt flavoring, calcium caseinate, ascorbic acid (vitamin C), reduced iron, niacinamide, zinc oxide, pyridoxine hydrochloride (vitamin B6), riboflavin (vitamin B2), thiamin hydrochloride (vitamin B1), vitamin A palmitate, folic acid, and vitamin D. Quality protected with BHT Item B-2% milk Reduced fat milk, vitamin A palmitate and vitamin D, added Item C―Lasagna with meat sauce Tomatoes (water, tomato paste), lasagna macaroni product (semolina, water, egg whites, glyceryl monstearate), cooked beef, sugar, corn oil flavoring, salt, parmesan cheese (pasteurized cultured milk, salt, enzymes), citric acid, spices, autolyzed yeast, hydrolyzed corn, soy, and wheat protein, olive oil, mushroom flavor (maltodextrin and mushroom juice powder) Item D-Canned green beans Green beans, water, salt (for flavor) Item E-Grilled chicken salad Lettuce, chicken tenders, tomatoes, carrots, celery, diced onions Item F-Basil vinaigrette dressing Soybean oil, balsamic vinegar (preserved with sulfites), olive oil, basil, water, high fructose corn syrup, sugar, salt, dehydrated garlic, spice, xanthan gum, iron, niacinamide, zinc oxide, pyri- doxine hydrochloride (vitamin B6), riboflavin (vitamin B2), thiamin hydrochloide (vitamin B1), vita- min A palmitate, folic acid, and vitamin D. Quality protected with BHT INSERT 2.8 Ingredient statements for items in Insert 2.7. 46 Introducing Food Science formulated foods with many ingredients. Note that some ingredients like the lasagna product have ingredients of their own, which are listed in paren- theses. Parentheses are also used to help explain the common names of some strange-sounding chemicals like the vitamins listed in the cereal and dress- ing. Each label must also include the company address of the distributor. This address is not necessarily where the product was manufactured. 2.15 Designing a Healthy Diet In developing a healthy diet, we want to get enough protein, vitamins, and minerals without getting too much fat, sugar, and sodium or too many calo- ries. Reliance on any one food is not a good idea, and it is best to eat a wide variety of foods in moderation. MyPlate (www.ChooseMyPlate.gov) is a useful tool to help us balance our diets and make healthier food choices (see Insert 2.9). MyPlate is designed to simulate a single dining setting with plate, fork, and cup. The plate is divided into four sections with grains and vegetable servings slightly larger than fruits and protein, thus indicating the proportionality of the servings. The cup suggests milk as the beverage of choice. MyPlate replaced MyPyramid in 2011 and represents a slight departure and simplification from previous guidelines. For example, while six groups were specified in MyPyramid (fruits, vegetables, grains, dairy, meat and beans, as well as oils), MyPlate is less restricted and allows inclusion of vegetarian diets and the website provides information on how to eat healthy on a budget and supplementary material including recipes, menus, and daily food plans. Overall, MyPlate (as well as previous programs) was developed to follow the Dietary Guidelines for Americans, a Federal initiative started on 1980. The Guidelines "encourage Americans to focus on eating a healthful diet—one INSERT 2.9 Dairy Fruits Grains Vegetables Protein Choose MyPlate.gov  MyPlate from http://ChooseMyPlate.gov (USDA 2014d). Healthiness of Foods 47 that focuses on foods and beverages that help achieve and maintain a healthy weight, promote health, and prevent disease." These guidelines are revised every 5 years and a new version is expected to be released in 2015. With obesity in an epidemic rise, it is never too early to adopt healthy food choices generation of children, and, in an effort to help the United States to raise a healthier federal efforts have expanded to encourage healthy eating at schools. In 2012, the USDA Food and Nutrition Service launched the Nutrition Standards in the National School Lunch and School Breakfast Programs, which was aimed to require "most schools to increase the avail- ability of fruits, vegetables, whole grains, and fat-free and low-fat fluid milk in school meals; reduce the levels of sodium, saturated fat and trans fat in meals; and meet the nutrition needs of school children within their calorie requirements." The standards address the most current nutrition guidelines and take into consideration the American school's situation. In summary, keeping in mind key words like variety and moderation, we are very fortunate to have access to a plentiful and safe food chain as well as information on which and how much of those foods to consume for a healthy life. It is then up to us to make healthy food choices! 2.16 Remember This! It is never too early to adopt healthy eating habits! The Nutrition Facts part of the label indicates the serving size, how many servings per container, calories per serving, and the fat calo- ries per serving.  Organic food production minimizes the input of fossil fuels and synthetic chemicals. Eating disorders occur when peer pressure clashes with biological needs. Fasting is self-starvation and can result in severe nutritional deficiencies. Nutraceuticals are foods specifically designed to act as drugs. There are few, if any, magical foods, but a balanced diet contributes to health and well-being, whereas a poor diet can lead to laziness, inattentiveness, and a bad attitude. There is no simple way to lose weight. Although food-borne diseases can be a concern, generally, though, when we talk about healthy foods, we are talking about foods that will help us avoid the diseases of civilization (cancer, diabetes, heart disease, and obesity). 48 Introducing Food Science Good nutrition requires an adequate consumption of nutrients with- out consuming too many calories. 2.17 Looking Ahead In the next chapter, we'll find how people decide what foods to eat. In Chapters 4 through 6, we will learn how the foods we find on supermarket shelves are processed or formulated. In Chapters 7 through 9, we will learn how food scientists ensure the quality and safety of foods, how they develop new products, and how the government regulates them. More detailed infor- mation on nutrition will be presented in Chapter 12. Testing Comprehension 1. Analyze the perspectives on diet and nutrition of Garrett, Jennifer, and Malik. Identify the strengths and weaknesses of their ideas. What potential health consequences could result from their approach? 2. List the differences between a healthy and an unhealthy food and between a healthy and an unhealthy diet. The authors suggest that we should focus our attention on the healthiness of the diet and not of individual foods. Describe and critique their rationale. 3. Provide three examples each of a natural food, an organic food, a processed food, and a whole food. Rank in order these four catego- ries of foods from healthiest to unhealthiest. Explain the reasons for this order. Would the authors of the book and the instructor of the class agree with this order? Why or why not? 4. Outline a personal nutritional strategy to maintain good health. What are the major barriers to implementing this strategy? How can these barriers be overcome? 5. Develop a 1-day meal plan for Jennifer that consists of whole foods and provides her with 1500-2000 calories, at least 100% of her Daily Value for calcium, iron, vitamin A, and vitamin C and no more than 100% of her Daily Value for fat and sodium. Analyze her plan for healthiness, cost, safety, and desirability. 6. Calculate the number of calories Malik consumed on the basis of the information provided in Insert 2.7 and the associated discussion in the text. Calculate the percentage of his calories that came from carbo- hydrate, fat, and protein as well as the %DV (Daily Value) for sodium, Healthiness of Foods protein, vitamins C and D, iron, calcium sodium, and dietary fiber. Assess the healthiness of his diet on the basis of these calculations. 7. List and describe the benefits and limitations of dietary supple- ments. Why do most dieticians recommend that we get our nutrients from foods and not supplements? What makes it so difficult to rely only on foods to get enough nutrients? 8. List and describe the nutritional consequences of fasting and the eating disorders described in the chapter. What obligation do we have when we see a friend or family member who is engaged in unhealthy eating practices? 9. Between the time this book was written and the time it is read, the Nutrition Facts statements will probably have had a makeover. Compare and contrast the labels show