Regarding eating and metabolism, research has shown that

A) overeating changes metabolism.
B) undereating changes metabolism.
C) both overeating and undereating can change metabolism.
D) metabolism is set by genetics and thus cannot be changed.

Both overeating and undereating can change metabolism. When a person overeats, their body stores excess calories as fat, which can lead to weight gain and an increase in metabolism to process the larger amount of food. In contrast, undereating can cause the body to slow down its metabolism in order to conserve energy, making it harder to lose weight or maintain a healthy weight. Therefore, both overeating and undereating can have a significant impact on metabolism.