Macronutrients-Individual Needs

Macronutrients

Once the total necessary calories have been calculated, the percentage of each macronutrient consumed per day should be determined.  Each patient is unique in regards to age, gender, height, weight, and activity level, thus every nutrition plan should reflect these factors in terms of caloric intake.

A macronutrient is a nutrient, such as a carbohydrate, fat, or protein that is needed in relatively large amounts in the diet.  Each macronutrient serves numerous functions in the body and is required in different percentages based on activity level.

The USDA Food Guide recommends that most adults consume 18% of their calories from protein, 29% from fat, and 53% from carbohydrates.  This is a general recommendation for sedentary to slightly active individuals (www.usda.gov is a good resource for practitioners to reference current information on the USDA's findings).

The average American diet consists of 50% of calories coming from carbohydrates (mainly from simple sugars), 34% from fat, and 16% from protein.  These ratios translate into too much fat, as 34% is much higher than the USDA's recommendation.  Too many calories contribute to the obesity epidemic seen in this country.

The Institute of Medicine Food & Nutrition Board established new dietary guidelines in 2002 for macronutrient consumption call the Acceptable Macronutrient Distribution Range (AMDR).  These guidelines were designed to avoid nutrient deficiencies that seem to occur when macronutrient consumption falls above or below the recommended levels.  The AMDR recommendations have been incorporated into the 2005 Dietary Guidelines for Americans and advocate 45-65% of their total calories from carbohydrates, 20-35% from fat, and 10-35% from protein.  These ranges are very similar to the USDA's Food Guide recommendations, but they also incorporate wider ranges that can be modified for different population groups like pregnant women, children, and adolescents.

Another population group that requires a modification in their macronutrient ratios is athletes. Research has shown that very athletic/endurance athletes (such as a marathon runner) can benefit from consuming 60-70% of their calories from carbohydrates, 15% from protein, and 10-15% from fat.  Very athletic/strength and power athletes (such as sprinters or football players) can benefit from consuming 55-65% of their calories from carbohydrates, 15-18% from protein, and 20-25% from fat.  These ranges vary according to varying activity level during training and or competition.

Exact macronutrient needs will vary according to activity level.  For example, people partaking in very strenuous activity may need a higher percentage of carbohydrates.