Chapter 13, Problem 3DWPA

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?

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.

Researchers set up an obesity study in which MZ and DZ twins who served in the armed forces were studied at induction into the military and 25 years later. Results indicated that obesity has a strong genetic component. a. What are some of the problems with this study? b. Design a better study to test whether obesity has a genetic component.