There are three important dietary macronutrients required each and every day: proteins, carbohydrates and fats. Protein intake is important to build muscle, repair tissues, and make the enzymes that digest food. Protein is part of the production and regulation of our hormones.
Protein is made up of 22 different amino acids. Nine of them are called essential amino acids because the body does not make them and they need to be consumed through our diet.
Dietary protein needs are higher at certain times including
- childhood and adolescence
- pregnancy and nursing
- older age because of increased rate of muscle breakdown
There are also differences in protein needs depending upon gender, weight, health, and level of physical activity.
An insufficient protein intake is unusual for most Americans but for various reasons, including intestinal malabsorption and a deficiency of digestive enzymes, there can be inadequate protein intake causing
- slow wound healing because collagen formation is compromised
- impairment of immune system, with increased risk for frequent infections
- weakening of bone structure
- hair loss
How much dietary protein do we need? Plan on 0.36 grams per one pound body weight to meet daily requirement. For example, a person who weighs 130 pounds would need 47 grams per day. Any adult over the age of 70 requires slightly more protein.
How do we meet our daily protein requirements? It helps to include protein at each meal because digestion and absorption are the most efficient when protein sources are spread throughout the day.
Animal protein sources include all nine essential amino acids: fish, poultry, red meat (beef, pork, veal, lamb) and eggs. These sources provide six to eight grams protein per one ounce. Dairy foods have all essential amino acids, too, since they are from an animal source: milk, yogurt and cheeses.
Vegetable protein sources do not contain all essential amino acids so we need a variety throughout the day to obtain those nine amino acids. Vegetable protein includes nuts and nut butters; seeds; legumes such as black beans, kidney beans, navy beans, lentils and split peas; soy foods such as edamame, tofu and tempeh (a fermented soy food); quinoa; green peas; whole-grains such as oats; and nutritional yeast.
There are lots of options for getting in your daily protein. For example:
- breakfast could be whole-grain English muffin or toast with an egg, melted cheese or peanut butter
- lunch can include a sandwich or whole-grain wrap with hummus, turkey bread or tuna salad
- dinner could be stir fry with beef cubes, shrimp or tofu cubes
About the Author
Rita Smith is a Registered Dietitian and Certified Diabetes Educator. She's been working in the field of nutrition and disease prevention for more than 35 years and currently works at Sentara Martha Jefferson Hospital in Charlottesville, Va. Each week, Rita provides nutrition counseling to clients who have a variety of disorders or diseases including high cholesterol, high blood pressure, diabetes, celiac disease, irritable bowel syndrome, gastroparesis and weight management. For these clients, food choices can help them manage their health problems.