On the box of Quaker Oatmeal it lists the calories as 150 for 1/2 cup dry. When cooking it according to directions (1 cup water and dash of salt), does the calorie amount change? This question could be applied to all foods where it lists a calorie amount for the dry form (noodles, pastas) but not for cooked.
When food moves from the uncooked state to the cooked state, the calories do not change; however, the food's weight can change as the food is cooked and, since calories are based on the food’s weight or volume, when the volume changes, the calories change too. Weight or volume changes as the food gains or loses water. Dry foods, like oatmeal and rice, gain volume, while wet foods, like meat and lose water weight. In terms of nutrients, some are damaged during cooking, while cooking liberates others. Calorie Count presents foods in the database in their cooked and raw forms.