All human bodies except newborns synthesize taurine from the amino acids methionine and cysteine (see Chapter 6), so although adults can make their own taurine, newborns need to get theirs from food, either breast milk or formula. That’s why its essential nature is conditional.
Boron: Several minerals, such as boron, are essential for plants but haven’t been proven essential for either microorganisms, such as bacteria, or for animals, including people.
For more on the vitamins and minerals, amino acids (the so-called building blocks of proteins), and fatty acids that are considered essential for your human body, check out Chapters 6, 7, 10, and 11.
Protecting the Nutrients in Your Food
Identifying nutrients is one thing. Making sure you get them into your body is another. What’s essential is keeping nutritious food nutritious by preserving and protecting its components.
Some people see the term food processing as a nutritional dirty word, or two words. They’re wrong. Without food processing and preservatives, you and I would still be forced to gather or kill our food each morning and down it fast before it spoiled. For more about which processing and preservative techniques produce the safest, most nutritious — and yes, delicious — dinners, check out Part 4.
Considering how vital food preservation can be, you may want to think about when you last heard a rousing cheer for the anonymous cook who first noticed that salting or pickling food could extend food’s shelf life. Or for the guys who invented the refrigeration and freezing techniques that slow food’s natural tendency to spoil.
Or for Louis Pasteur, the man who made it absolutely clear that heating food to boiling kills bugs (microorganisms) that might otherwise cause food poisoning. So give them a hand, right here.
Knowing Your Nutritional Status
Nutritional status is a phrase that describes the state of your health as related to your diet. Malnutrition is what happens when the diet goes wrong. Most people think of malnutrition as the result of diet too low in calories and essential nutrients, such as vitamins, but a diet that delivers too much food leads to malnutrition in the form of obesity. The latter is more common in developed countries with an abundant food supply and a relatively sedentary population. The former may arise from
A diet that simply doesn’t provide enough food: This situation can occur in times of famine or through voluntary starvation due to an eating disorder or because something in your life disturbs your appetite. Among older people, malnutrition may follow tooth loss or age-related loss of appetite or because they live alone and sometimes just forget to eat.
A diet that, while otherwise adequate, is deficient in a specific nutrient: This kind of nutritional inadequacy can lead to a deficiency disease, such as beriberi — the disease caused by a lack of vitamin B1 (thiamine).
A metabolic disorder or medical condition that prevents your body from absorbing specific nutrients, such as carbohydrates or protein: One common example is diabetes, the inability to produce enough insulin, the hormone your body uses to metabolize (digest) carbohydrates. Another is celiac disease, a condition that makes it impossible for the body to digest gluten, a protein in wheat. Need more info on either diabetes or celiac disease? Check out Diabetes For Dummies, by Alan L. Rubin; Diabetes Meal Planning & Nutrition For Dummies, by Toby Smithson and Alan L. Rubin; and Gluten-Free All-in-One For Dummies, a five-books-in-one bargain on living with celiac disease (all books published by Wiley).
Doctors and registered dietitians have many tools with which to rate your nutritional status. They can
Review your medical history to see whether you have any conditions (such as dentures) that may make eating certain foods difficult or that interfere with your ability to absorb nutrients.
Perform a physical examination to look for obvious signs of nutritional deficiency, such as dull hair and eyes (a lack of vitamins?), poor posture (not enough calcium to protect the spinal bones?), or extreme thinness (not enough food? an underlying disease?).
Order laboratory blood and urine tests that may identify early signs of malnutrition, such as the lack of red blood cells that characterizes anemia caused by an iron deficiency.
Fitting Food into the Medicine Chest
Food is medicine for the body and the soul. Good meals make good friends, and modern research validates the virtues not only of Granny’s chicken soup but also of heart-healthy sulfur compounds in garlic and onions, anticholesterol dietary fiber in grains and beans, bone-building calcium in milk and greens, and mood elevators in coffee, tea, and chocolate.
Of course, foods pose some risks as well: food allergies, food intolerances, food and drug interactions, and the occasional harmful substances, such as the dreaded saturated fats and trans fats (see Chapter 7). In other words, constructing a healthful diet can mean tailoring food choices to your own special body, which is the subject of Part 5.
Finding Nutrition Facts
Getting reliable information about nutrition can be a challenge. For the most part, you’re likely to get your nutrition information from TV and radio talk shows or news, your daily newspaper, your favorite magazine, a variety of nutrition-oriented books, and the Internet.
If you’re not a nutrition expert, how can you tell whether what you hear or read is really right? By looking for the validation from people who are, of course, and by knowing what questions to ask.
Nutrition people
Not every piece of nutrition news is nutritious. The person who makes the news may simply have wandered in with a new theory — “Artichokes cure cancer!” “Never eat cherries and cheese at the same meal!” “Women who take vitamin C are more likely to give birth to twins!” The more bizarre, the better.
Those most likely to give you news you can use with confidence are
Nutrition scientists and researchers: These are people with undergraduate or graduate degrees in science subjects, such as chemistry, biology, biochemistry, or physics, and are engaged in research dealing primarily with the biological effects of food on animals and human beings. Some nutrition investigators come from other fields entirely, such as a historian or sociologist, whose research concentrates on food history and habits.
Dietitians and nutritionists: These people have undergraduate degrees in food and nutrition science or the management of food programs. A person with the letters RD (registered dietitian) after his name has completed a dietetic internship and passed an American Dietetic Association licensing exam. In some states, a person who claims the title “nutritionist” must have a graduate degree in basic science courses related to nutrition.
Nutrition reporters and writers: These are people who specialize in giving you information about the medical and/or scientific aspects of food. Most have the science background