Answer to Question 1
Vitamins fall into two categories: those that dissolve in water (water-soluble vitamins) and those that dissolve in fat (fat-soluble vitamins). To date, scientists have identified 13 vitamins, each with its own special roles to play. Each of the food groups in the MyPlate food guide supplies a number of vitamins. Eating plans that exclude entire food groups or fail to include the amounts of food from each group may lead to vitamin deficiencies over time.
The nine water-soluble vitaminseight B vitamins and vitamin Care found in the watery components of foods, such as the juice of an orange. These vitamins are distributed into water-filled compartments of the body, including the fluid that surrounds the spinal cord. The body excretes excess water-soluble vitamins if blood levels rise too high. As a result, these vitamins rarely reach toxic levels in the body. This is not to say, however, that excess levels cannot cause problems, at least in some people.
In contrast, the four fat-soluble vitaminsA, D, E, and Kare generally found in the fats and oils of foods. Because they are stored in the liver and in body fat, it is possible for megadoses of fat-soluble vitamins to build up to toxic levels in the body and cause undesirable side effects.
Answer to Question 2
C
