Your body needs a blend of carbohydrates, protein and fat to fuel its physical activity and metabolic needs. While there is no perfect balance for everyone, the Food and Nutrition Board of the Institute of Medicine provides a range of your total caloric intake that is acceptable for each nutrient. Known as the acceptable macronutrient distribution range, this guideline can help you plan your diet.
Carbohydrates and Sugar
According to the IOM, carbohydrates should comprise 45 to 65 percent of your total caloric intake. For a 2,000-calorie diet, this range amounts to 900 to 1,300 calories per day. Sugar, is a simple carbohydrate that can be both bad and good for the diet. Natural fruit and plant sugars are beneficial, but added sugars, such as those found in soft drinks, can increase the risk of diabetes and weight gain. Added sugars should be restricted to 5 to 15 percent of total caloric intake, according to MayoClinic.com.
Protein should comprise 10 to 35 percent of your total caloric intake, according to the IOM. A 2,000-calorie diet should therefore include 200 to 700 calories from this nutrient. The AMDR for protein is much wider than the other two macronutrients and is highly dependent on activity level. Athletes and other highly active individuals should consume a greater amount of protein to restore damaged muscular tissue and promote the synthesis of new tissue, erring on the higher end of the AMDR.
According to the IOM, fat should account for 20 to 35 percent of your total caloric intake, amounting to 400 to 700 calories a day for a 2,000-calorie diet. Like the other two macronutrients, fat is essential to the diet and helps store vitamins, protect organs and provide energy. Extreme low-fat diets are unhealthy and can lead to decreased hormone production and damage to vital organs.
The Ideal Blend
Because specific nutrient requirements are dependent on a number of individual factors, it's difficult to provide specific percentage recommendations. Renowned British track and field coach Brian Mackenzie believes that the ideal blend for athletes is to consume 57 percent of your total calories from carbohydrates, 30 percent from fat and 13 percent from protein. Other fitness professionals commonly recommend a simple 50/30/20 blend (i.e., 50 percent carbohydrates, 30 percent fat and 20 percent protein). Nevertheless, any blend that falls within the IOM's AMDR will ensure adequate nutrition.