Foods to Have:
Beef* 3 ounces
Eggs (white)** 3 egg whites
Milk** 1 cup
Soy* 1 cup
Whey* 1 ounce
*The protein digestibility-corrected amino acid score (PDCAAS) for isolated soy is the same as the protein in eggs, whey, and milk. Whole soy foods and beef scored lower on the PDCAAS scale.
**Highest in PDCAAS
Also consider: Poultry, nuts, beans, grains
What is protein and what are the best protein foods?
Protein is needed to build and repair muscle tissue, but it's also integral to cranking out enzymes and hormones that help support every cell and system in our body, from digestion to immunity. Protein is made up of individual building blocks called amino acids. And if needed in a pinch, they can supply the body with energy, too.
Protein can be found in both animal and plant sources. Although they differ in quality, both kinds of proteins can meet the needs of the average American. There are twenty amino acids that humans need each and every day, nine of which are considered indispensible yet which cannot be manufactured by the body. This is only a concern with diets that are made up entirely of plant-based proteins. Vegans, who consume no animal products, must be careful to include complementary proteins in their diet (e.g., grains and beans). When combined, these plant proteins supply all nine indispensible amino acids. Other forms of vegetarianism are not a concern because even the smallest amount of meat, fish, or dairy products added to incomplete plant proteins makes them complete.
Did you know?
The quality and timing of protein are important for those who are more performance and athletically inclined. Here, you have used the internationally accepted method of ranking protein quality, called the protein digestibility-corrected amino acid score (PDCAAS): Proteins are ranked based on whether they contain all of the indispensible amino acids and also by their rate of digestibility. For athletes, sports nutrition experts recommend that a high-quality protein be consumed within two hours of exercise, a period of time called the anabolic window, which favors optimal protein synthesis.
How much is enough?
Level of activity - Recommended Daily Protein Intake (per kg of body weight)
Sedentary adults 0.8 g/kg
Recreational athletes* 1.0 g/kg
Endurance athletes 1.2–1.4 g/kg
Ultraendurance athletes 1.2–2.0 g/kg
Strength athletes 1.2–2.0 g/kg
*Low to moderate training volume and intensity.
Beef
Sarcopenia is a condition of muscle wasting that occurs as early as the mid-forties, which is estimated to increase the risk of disability later in life by three- to fourfold. The current dietary reference intake of 0.8 g of protein per kilogram of body weight may not be enough, according to some protein researchers, to stave off this condition. A 3-ounce portion of beef provides about 25 g of protein (51 percent of the DV). Another study found that consuming 4 ounces of lean beef protein each day can help enhance muscle development by 50 percent and delay the onset of sarcopenia or loss of muscle. Eating at least 15 g of essential amino acids at each meal, equivalent to 4 ounces of a high-quality protein, such as lean meat, may help maintain muscle mass and provide strength to lead an active lifestyle.
Eggs
Don't get the yolk? Boy, are you missing out. Eggs whites are only half the story, as yolks provide almost half the protein in eggs, plus most of the nutrients ! And starting the day with a few whole eggs may help you on the scale later on, as research suggests that the protein in eggs provides satiety and can spell calorie savings at the end of the day, due to reduced cravings for snacks plus a smaller appetite overall.
Milk
Milk is an excellent source of numerous vitamins and minerals . A variety of factors contribute to increased risk of osteoporosis, including low calcium intake, low physical activity, being overweight or too thin, and genetics, to name a few. Besides ingesting adequate calcium to build up bone stores when we are young, consuming calcium along with other cofactors that can aid in absorption is equally important. The greatest contributor of calcium to the American diet is dairy, which also provides vitamin D (thanks to fortification) as well as other conutrients that help drive calcium into bones. Of particular interest here is the role of bioactive protein components that naturally occur in milk, which enhance calcium absorption. Dairy also contains a unique blend of slow-acting (casein) and fast-acting (whey) proteins—an ideal combo to ingest postexercise, as whey supplies an immediate source of amino acids to aid in muscle recovery, while casein helps slow down the rate of muscle breakdown.
Soy
Isolated soy protein powder can go head to head with some of the big boys mentioned here; however, whole soybean foods, though containing all of the nine indispensible amino acids, don't score as high on the PDCAAS chart. That said, cooked soybeans are supernutritious , and still provide a decent dose of protein.
Whey
Whey and casein are the two major proteins found in milk. During the cheese-making process, whey is separated from the cheese curds when enzymes are added to the milk. Then the liquid whey is dried and sold in powder form. Historically, the liquid whey would be fed to animals or discarded. Now whey is valued as one the highest protein sources on earth! A serving of whey is an excellent source of protein and a good source of calcium. The amino acid profile of whey protein closely resembles that of skeletal muscle in the body. In fact, whey provides an excellent amount of branched-chain amino acids (BCAAs) vital for muscle repair. Whey is also rich in the amino acid glutamine, which helps reduce muscle breakdown and bolsters glutathione production in muscles and the liver, which in turn enhances immune function. A double-blind, randomized clinical trial of ninety overweight or obese subjects found that the group that consumed 56 g of whey protein per day for twenty-three weeks reduced their body weight by an average of 4 pounds and body fat by an average of 5 pounds, while also reducing their waist circumference and the hunger-stimulating hormone ghrelin. The interesting thing about the study is none of the groups were instructed to change anything about their diets.