Macronutrients: Protein
What are macronutrients?
Macronutrients are the nutrients that your body needs in large amounts, which include fat, carbohydrates, and protein. They give you energy and contain the components of food that your body needs to maintain its systems and structures. You need all three macronutrients as part of a healthy diet, so you shouldn't exclude or seriously restrict any of them.
What Is Protein?
Protein is found throughout the body in muscle, bone, skin, hair, and virtually every other body part or tissue. It makes up the enzymes that power many chemical reactions and the hemoglobin that carries oxygen in your blood. At least 10,000 different proteins make you what you are and keep you that way. Protein is essential to many of your body's functions, including:
• Tissue structure
• Hormone system
• Metabolic system
• Transport system
• Enzymes that regulate metabolism
• Balancing the acid/base environment
Protein is made from twenty-plus basic building blocks called amino acids. Because we don't store amino acids, our bodies make them in two different ways: either from scratch, or by modifying others. Nine amino acids, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine, are known as the essential amino acids, meaning that we must getthem from food.
What are “complete” proteins?
“Pure” protein, whether derived from plant or animal foods, probably has similar effects on health, although the mix of amino acids can have health implications. Some proteins found in food are “complete,” meaning they contain all twenty-plus types of amino acids needed to make new protein in the body. Others are incomplete, lacking one or more of the nine essential amino acids, which our bodies can't make from scratch or from other amino acids. Animal-based foods (meat,
poultry, fish, eggs, and dairy foods) tend to be good sources of complete protein, while plant-based foods (fruits, vegetables, grains, nuts, and seeds) often lack one or more essential amino acid. Those who abstain from eating animal-based foods can eat a variety of protein-containing plant foods each day in order to get all the amino acids needed to make new protein, and also choose to incorporate complete plant proteins like quinoa or chia seeds.
What are the general recommendations for protein intake?
Age Group | Age Range | Daily Recommendations in Ounce-Equivalents (oz-equiv) |
|---|---|---|
Toddlers | 12 to 23 months | 2 oz-equiv |
Children | 2 to 4 years
5 to 8 years | 2 to 5 oz-equiv 3 to 5 ½ oz-equiv |
Girls | 9 to 13 years
14 to 18 years | 4 to 6 oz-equiv 5 to 6 ½ oz-equiv |
Boys | 9 to 13 years 14 to 18 years | 5 to 6 ½ oz-equiv 5½ to 7 oz-equiv |
Women | 19 to 30 years 31 to 59 years
60+ years | 5 to 6½ oz-equiv
5 to 6 oz-equiv
5 to 6 oz-equiv |
Men | 19-30 years
31-59 years
60+ years | 6½ to 7 oz-equiv
6 to 7 oz-equiv
5½ to 6½ oz-equiv |
What is an ounce-equivalent (oz-equiv)?
Food | Amount that counts as 1 oz-equiv in the Protein Foods Group |
|---|---|
Meats | • 1 ounce cooked lean beef, goat, ham, lamb, or pork
• 1 ounce cooked lean ground beef or pork
• 1 slice of luncheon or deli meats (beef, chicken, ham, pork, turkey)
• 1 ounce cooked game meats (bear, bison, deer, elk, moose, opossum, rabbit, venison)
• 1 ounce cooked organ meats |
Poultry | • 1 ounce cooked (without skin) chicken, ostrich, or turkey
• 2 ounces cooked Cornish hen, duck, goose, pheasant, or quail
• 1 sandwich slice of turkey or chicken breast (4½" x 2½" x ⅛") |
Seafood | • 1 ounce cooked finfish (black sea bass, catfish, cod, flounder, freshwater trout, haddock, hake, halibut, herring, light tuna, mackerel, mullet, perch, pollock, salmon, sea bass, snapper, sole, tilapia, whiting)
• 1 ounce cooked shellfish (clams, crab, crayfish, lobster, mussels, octopus, oysters, scallops, shrimp, squid (calamari)
• 1 ounce canned fish (anchovies, freshwater trout, herring, light tuna, salmon, sardines) |
Eggs | • 1 egg
• 1½ egg whites (or 3 tablespoons liquid egg white product) |
Nuts and Seeds | • ½ ounce of nuts (12 almonds, 24 pistachios, 7 walnut halves)
• ½ ounce of seeds (chia, flax, pumpkin, sesame, sunflower, or squash seeds) hulled, roasted
• 1 tablespoon of almond, cashew, peanut, or sunflower butter, or sesame paste (tahini) |
Beans, peas, and lentils | • ¼ cup of cooked beans, peas or lentils (such as bayo, black, brown, fava, garbanzo, kidney, lima, mung, navy, pigeon, pink, pinto, or soy, or white beans, or black-eyed peas (cow peas) or split peas, and red, brown, and green lentils)
• ¼ cup of baked beans or refried beans
• ¼ cup (about 2 ounces) of tofu
• 1 oz. tempeh, cooked
• ¼ cup soybeans, cooked
• 1 falafel patty (2 ¼", 4 oz)
• 6 tablespoons hummus |
Why is it important to eat lean or low-fat proteins?
Lean or low-fat proteins provide nutrients that are vital for the health and maintenance of your body. Many Americans meet the protein recommendations for meat,
poultry, and eggs, but do not meet the recommendations for seafood or nuts, seeds, and soy products. By varying your proteins, it can help increase intake of important nutrients, including unsaturated fats, dietary fiber, and vitamin D and help to limit intake of sodium and saturated fats coming from processed meat and poultry. Some proteins are high in saturated fat, and it is recommended to limit the amount that you eat. Examples include fatty cuts of beef, lamb, or pork; regular (75-85% lean) ground beef; regular sausages, hot dogs, and bacon; some lunch meats like bologna or salami; and some poultry like duck.
What are the health benefits of protein?
• Proteins function as building blocks for bones, muscles, cartilage, skin, and blood. They are also building blocks for enzymes, hormones, and vitamins. Proteins are one of three nutrients that provide calories (the others are fat and carbohydrates).
• Nutrients provided by various protein foods can differ. Varying your protein food choices can provide your body with a range of nutrients designed to keep your body functioning well. B vitamins help build tissue and aid in forming red blood cells. Iron can prevent anemia. Magnesium helps build bones and supports muscle function. Zinc can support your immune systems.
• EPA and DHA are omega-3 fatty acids found in varying amounts in seafood. Eating 8 ounces per week of seafood may help reduce the risk for heart disease.
Sources:
https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/protein/
https://www.mdanderson.org/publications/focused-on-health/what-are-macronutrients-.h15-1593780.html
https://www.myplate.gov/eat-healthy/protein-foods