Protein Calculation From The Rda

The main course of a meal is usually a protein-rich food such as meat, fish, eggs and milk. Most plant foods, with the notable exception of soybeans, lack one or more of the essential amino acids to be considered a complete protein, but eating a combination of vegetarian foods enables one to obtain all the essential amino acids and meet dietary requirements. The recommended dietary allowance, or RDA, for protein varies with age and weight.

Protein Needs

Protein is present in all cells of the body and is the only nutrient that is essential for building and maintaining body tissues and cells. For this reason, infants, children and adolescents need more protein as they grow to their age-appropriate heights and weights. Similarly, protein requirements increase during pregnancy, to accommodate the growth of the fetus, and during lactation, for milk production. In adults, protein needs are constant, as the main function of protein is to maintain body tissues and cells.

RDA for Protein

Recommended dietary allowance (RDA) for proteins are based on requirements per kilogram of body weight. (If you know your weight in pounds, convert it to kilograms by dividing it by 2.2.) Both adult males and females between the ages of 19 to 50 require 0.8 grams of protein per kilogram of body weight every day or 0.8 g/kg/d, according to the Institute of Medicine's Food and Nutrition Board. Requirements for children between the ages of 1 to 3 years are 1.05 g/kg/d, while needs decrease to 0.95 g/kg/d for those between the ages of 4 to 13. Adolescents between the ages of 14 to 18 years require less protein than younger children and have a requirement of 0.85 g/kg/d.

Calculating Your Protein Requirements

Before calculating your protein requirements, weigh yourself on an accurate scale. If you are between the ages of 19 to 50, multiplying your body weight in kilograms by 0.8 will give you your daily requirement for protein, according to the Food and Nutrition Board. As an example, the daily protein requirement for a 21-year-old woman who weighs 54 kg, is calculated by multiplying 54 by 0.8, which equals to 43.2 grams of protein.

Calculating Protein Requirements during Pregnancy and Lactation

During pregnancy, requirement for proteins are 1.1 g/kg/d, according to the Food and Nutrition Board. To put that in perspective, a 54 kg pregnant woman needs 59.4 grams of protein daily, which is obtained by multiplying 54 by 1.1. Similarly, a 54 kg lactating woman requires 1.3 g/kg/d of protein, which comes to a daily protein requirement of 70 grams.