Chapter 7, Problem 6RQ

Which of the following statements is not true? a. Essential nutrients can be synthesized by the body. b. Vitamins are required in small quantities for bodily function. c. Some amino acids can be synthesized by the body, while others need to be obtained from diet. d. Vitamins come in two categories: fat-soluble and water-soluble.

The food label in Figure 11.28 lists the nutrients and other substances in a package of ready-to-eat macaroni and cheese. Based on your reading in this chapter, how would you rate this products healthiness in terms of fats and carbohydrates? Figure 11.28 Food labels are useful health tools. Information on a food label can be used to ensure that you get the nutrients you need without exceeding recommended limits on less healthy substances such as salt, sugar, and trans fats. At present, the USDA is considering major revisions to food labels. The proposed changes include showing realistic serving sizes and sugars added by the manufacturer, and printing the calorie content per serving in larger, bolder type so that it is easier for consumers to make informed choices about purchases of prepared foods. (Left: USDA, US Department of Agriculture; Right: FoodCollection/SuperStock)

Some nutritionists claim that the secret to long life is to be slightly underweight as an adult. If a persons weight is related partly to diet, partly to activity level, and partly to genetics, what underlying factors could be at work to generate statistics that support this claim?