A Calorie or kilocalorie (sometimes kcal, C, Cal or less accurately calorie or cal) is a unit of energy; it is equal to 4185.5 Joules or 3.968 Btu. Calories provide the energy needed for growth and activity.
Like proteins, carbohydrates provide 4 calories per gram. Foods with high concentrations of carbohydrates are sweet or starchy, such as sugars, honey, fruits, rice, pasta, potatoes, and bread. Consuming primarily refined carbohydrates can lead to higher overall calorie intake because refined carbohydrates do not suppress appetite as well as proteins and fats do.
Alcohol provides 7 calories per gram, but it is not recommended as a dependable source of energy, due to health problems related to its over-consumption.
Some people may decrease their caloric intake for health-related reasons or out of a desire for weight loss. Decreasing caloric intake can be done through reducing the overall amount of food one eats, switching to lower-calorie foods, or a combination of both methods.
Some people may need to increase their caloric intake for short-term energy yield or long-term weight gain.
One can easily increase the calorie content of a dish by adding oil and fat. A tasty way to do this is by frying food; in particular the deep-fat method adds a large amount of fat to food. Oil can also be added to many soups without greatly affecting their taste or texture.
Normally low-calorie foods such as vegetables can be enhanced by adding cheese, salad dressing, and gravy. Fruits can be treated with cream or chocolate. Many snack foods, such as pretzels and crackers, can be dipped in butter or peanut butter.
When increasing caloric intake for a shorter-term jolt of energy (such as for running a race), increased consumption of fats is not recommended. Typically, in the day or two before the needed energy boost, one should consume a larger amount of carbohydrates.