Who should read this chapter? Parents who have teenagers.
Summary: Teens should optimally transition from a diet that maximizes their growth potential during their adolescent growth spurt to a diet that minimizes obesity risk once their vertical growth has stopped. This involves a diet change from one high in protein to one that is high in fruits and vegetables.
When children are young, it is more important for them to grow tall (assuming you want this, since a few parents actually want their children to be shorter) rather than to be chubby. As an adult, we aren't able to grow taller anymore, but we have lots of opportunities to continue to grow sideways (i.e., become chubby). Since children are much more active than adults, maintaining the eating habits acquired during childhood will result in an obese adult, since the voracious appetite of an active teen is excessive for a less active adult.
High protein and high calorie diets should be maintained by teens during their adolescent growth spurt to maximize height potential. Once teens stop growing taller and their height potential is reached, they should be encouraged to modify their diets to eventually adopt a more adult-healthy diet. They should be encouraged to take in less protein (meat, chicken, eggs, etc.), less starch and fat, but more fruits and vegetables. Teens that make this transition well, are less likely to become overweight adults.
Most growing teens are used to eating high protein foods and fast foods. Their experience with vegetables and fruits is generally of a limited variety. When transitioning teens to a healthier adult diet, they should be introduced to a greater variety of fruits and vegetables. New fruits such as Kiwi fruit, plums, papayas, tangelo, mango, lychee, nectarines, guavas, etc., should be tried. Different vegetables in different types of salads with a greater variety of dressings should be introduced. As an adult, I really learned to like Caesar salads, baby lettuce greens and peppers.
An interesting observational study can be done by going to a cafeteria and observing what people have on their trays at the cashier. You will generally find that obese people have roast beef, gravy, extra mashed potatoes, corn, and a Diet Coke. Remember that corn is a starch (high calorie). True, corn is a vegetable and it is crunchy, but it is similar to rice and potatoes. The Diet Coke is interesting, but the calorie savings here are tiny compared to what's on the plate. Slender people order the chicken entree, one scoop of rice or mashed potatoes, a vegetable salad, sometimes soup and a drink. The vegetable salad fills them up without adding much calories. The chicken entree is still high calorie, but the overall lunch is much lower in calories than the beef entree with three scoops of mashed potatoes.
There are interesting "justifications" for what people eat. "Mashed potatoes have no cholesterol so I can eat as much of this as I want to." True, mashed potatoes have no cholesterol, but as with any starch, it is high in calories, which the human body stores as body fat. The excess body fat negatively affects your body's lipid profile so although potatoes have no cholesterol and almost no fat, it still impacts on body fat and cholesterol.
"I'll eat complex carbohydrates so I can eat more." Complex carbohydrates such as pasta are better than starches and sugar, but only minimally so. Complex carbohydrates are similar to starches. They are high in calories and when consumed, are utilized as energy fuel for body activity, but the excess is stored as body fat.
"I'll have the vegetarian dish." Vegetarian entrees may be healthy, but vegetarian dishes made with lots of cheese, eggs and starch may be high in calories, fat and cholesterol. Vegetarian lasagna is made mostly of cheese and pasta. Cheese ravioli is similar. Spinach pasta may be green, but it is largely pasta and cheese. Omelets, biscuits, bagels, grilled cheese sandwiches, rolls, pies, cakes and ice cream are all non-meat dishes which are high in calories. True vegetarian dishes made without eggs and cheese are lower in fat, calories and cholesterol.
"I'll eat soup and a salad for lunch." Not all soups are created equally. Chunky soups with lots of meat and starch are more like beef stew than soup. Creamy soups are laced with fat, starch and carbohydrates. Creamy soups should be considered similar to gravy. Clearer watery soups that are less chunky or contain mostly vegetables are lower in fat and calories. A low calorie salad consists of vegetables such as lettuce, tomatoes, sprouts, broccoli, cabbage, celery, carrots and peppers with an Italian dressing. A high calorie salad consists of pasta, beans, baby potatoes, corn, cottage cheese, beets, olives, grated cheese, artichoke hearts with a creamy dressing (such as Ranch, Caesar, Thousand Island, Blue Cheese, etc.). This type of high calorie salad can exceed the calorie content of a typical meal. Using the cafeteria observation study, examine the types of salads that slim and obese people are purchasing at the cafeteria cashier check-out. You will find high calorie salads purchased by obese people and low calorie salads purchased by slim people.