Daily Caloric Intake Requirement

Your daily caloric intake requirement is the amount of calories necessary to meet your energy needs. An individual's energy needs vary depending on factors such as age, weight and activity level. All of these factors influence your resting metabolic rate, which is the biggest predictor of the amount of calories you burn in a day. Useful formulas exist to help you determine your needs.

Metabolism

Your basal metabolic rate is the amount of calories required to perform basic functions of metabolism, including breathing, synthesis of hormones and other compounds, and cell growth and regeneration. This accounts for as much as 80 percent of your daily caloric expenditure. In addition, physical activity from household chores to marathons increases your caloric expenditure. Finally, the food you eat increases your metabolic rate temporarily. This is called the thermic effect of food and accounts for 5 to 10 percent of total calories burned.

Harris Benedict Equation

Various methods for calculating your caloric needs exist. One of these is the Harris Benedict Equation. This formula uses your basal metabolic rate based on your age, height and weight and multiplies it by an activity factor. By this equation, extra active individuals require more than 60 percent more calories each day than those with little or no daily exercise. Several websites exist that allow you to use the Harris Benedict Formula to determine your metabolic needs.

A Simpler Method

Other methods exist that provide a rough estimate of your daily caloric intake. One of simplest is to take your weight in pounds and multiply it by a constant based on your activity level. If you are sedentary, or get little or no exercise, multiply your weight in pounds by 30. If you are moderately active, defined as 30 minutes of exercise five days per week, multiply your weight in pounds by 35. Very active individuals should multiply by 40. Using this equation, a 150-lb. person requires between 2,000 and 2,700 calories based on activity level.

Considerations

Assuring you meet your caloric requirements is only one aim of proper nutrition. Calories come in three major forms: carbohydrates, protein and fat. Each serves specific cellular functions, and a proper balance is essential for good health. The United States Department of Agriculture recommends getting 10 to 35 percent of calories from protein, and choosing polyunsaturated fats over trans fats, saturated fats and cholesterol. Carbohydrates provide energy, but choose natural sugars found in fruits over added sugars present in soft drinks and candy.