Protein Content: 15 to 20 g per 6-ounce serving
All dairy products are good sources of protein. A glass of milk provides you with 8 g, but Greek yogurt is a protein powerhouse, with twice the protein and half the sugar and carbs of regular yogurt. In fact, Greek yogurt contains the same protein as a three-ounce serving of lean meat. Top that with a handful of nuts and you could get half of your daily protein intake at breakfast. Mixing different vegetarian protein sources into your daily routine also insures that you're getting the right mixture of amino acids, which aid in building muscle and regulating your metabolism.
Protein Content: 4 g per avocado
All vegetables contain between 1 and 2 g of protein per cup, but avocados (which are technically fruits) surpass them all. Though 4 g may not sound like much, avocado protein contains all nine essential amino acids, the amino acids your body can't produce on its own to build muscle and create more protein, in addition to heart- and brain-healthy omega-3 fatty acids.
There may even be a reason these fruits are in season during flu season. "Protein not only builds muscle and maintains organ structures, but is also needed to mount prompt, strong immune responses," explains Carol S. Johnston, professor and director of the nutrition program at Arizona State University's College of Nursing and Health Innovation. "You want to have adequate protein intake daily to have amino acids ready for immune protein synthesis at the time of infection."
Protein Content: 5 to 7 g of protein per cup, cooked
There are grains, and then there are pseudograins. Grains, wheat, barley, rye, brown rice and corn, all contain decent amounts of protein, and globally, wheat provides more plant-based protein than any other food. But intolerance to the gluten in wheat, barley, and rye is on the rise, owing to the increased use of these grains in processed foods. So if you want to go gluten free, look to corn, rice, and pseudograins, foods that are cooked and served like grains but are technically seeds, including quinoa, amaranth, buckwheat, millet, and wild rice. If you stick with corn, replace the standard yellow or white corn products with blue corn, which has 30 percent more protein.
Humanely Raised Beef
Protein Content: between 20 and 25 g per 3-ounce serving, depending on cut
OK, so beef isn't vegetarian, but you don't have to give up meat entirely to get heart-, brain-, and planet-friendly protein. The UN report finding that factory-farming was so bad for the planet also noted that improving animal diets and getting them off of grain was one huge step meat producers could take to counteract global warming. In other words, feeding animals their natural diet of grass and forage is better for our climate than pumping cattle full of corn and soy, which increase "enteric fermentation," or, basically, flatulent cattle that produce methane, a potent greenhouse gas. That diet also produces healthier beef. Grass-fed meats routinely show higher levels of omega-3 fatty acids and other vitamins, as well as lower levels of E. coli, than factory-farmed beef. Shop for grass-fed beef at your local farmer's market, or order it online through U.S. Wellness Meats.
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