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    11 Surprising Facts About Eating Protein

    Number One: You probably don't need to add any extra to your diet.


    1. Good news: You're probably already getting more than enough protein!

    Most Americans' diets include more protein than they actually need. Protein should make up 10 to 15% of your daily calorie intake, according to the World Health Organization. That comes out to 46 grams per day for most adult women, and 56 grams for most adult men, according to the Centers for Disease Control and Prevention. But most people overshoot that target: A National Health and Nutrition Examination Survey found that American men are consuming an average of 101.9 grams a day, and women an average of 70.1 grams. A single skinless chicken breast, with 54 grams of protein, would satisfy your daily quota.

    2. And yes, this is true for most vegetarians and vegans — if they're eating whole foods.

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    "If you are a vegan or vegetarian and you're eating a lot of refined or processed products, you may not be getting enough protein," says RDN Frances Largeman-Roth, author of Eating In Color: Delicious Healthy Recipes For You and Your Family. But if you're eating a good variety of whole foods, she says, you probably are. "It's really a misconception that you can't get enough protein. It's just that you're not sitting down having a steak, which might have 30 to 40 grams in one sitting."

    Because vegans aren't eating any animal products, they have to pay special attention. "If you follow vegan practices, you need to be sure to eat a variety of grains and beans (to get enough protein), to take in enough calories (so you don't lose weight), and to find an alternative source for vitamin B12 (the one vitamin that is found only in foods from animal sources)," advises Marion Nestle in her book What To Eat. You can find B12 in some kinds of nutritional yeasts, some fortified soy milks, supplements, and some fake meat products. Just check your nutritional labels to be sure.

    Looking for some meatless, high-protein recipes? Here are some ideas for vegans and vegetarians both.

    3. Athletes need more protein than the rest of us, but how much varies from person to person.

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    Athletes (meaning someone working out at high intensity five times a week) need more protein than the average person, but how much depends on their sex, their level and type of activity, and other variables. An adult male athlete may need 84 to 119 grams per day, and an adult female athlete may need about 66 to 94 grams, according to the Academy of Nutrition and Dietetics.

    If you're a regular person working out a few times a week for an hour or less each time, you probably don't need to worry about getting additional protein. If you're more active, talk to a registered dietitian nutritionist to find out what your protein needs are.

    4. You can get all the protein you need from plant-based foods.

    Proteins are made up of amino acids, and our bodies can produce 11 of the 20 amino acids we need all by themselves. The other nine are known as "essential" amino acids, because we need to get them from our diets. Foods that contain all nine of these acids are referred to as "complete proteins."

    Animal-based foods, like beef, poultry, eggs, and cheese, are considered complete proteins. But so are some plant-based foods like quinoa, soy, buckwheat, and chia seeds. And certain combinations of vegetarian foods (rice and beans, peanut butter and whole wheat bread) can also give you your full helping of amino acids.

    5. You don't need to get all of your amino acids from a single food, or even a single meal.

    "Research indicates that an assortment of plant foods eaten over the course of a day can provide all essential amino acids," says the the Journal of the American Dietetic Association. "Thus complimentary proteins do not need to be consumed at the same meal."

    What's important, says Largeman-Roth, is that you incorporate a variety of whole foods into your diet so you hit all the amino acids at some point throughout the day.

    6. Some sources of protein may surprise you.

    Lots of vegetables and grains are good protein sources, even though they don't have all of the amino acids. Peas, for example, have 9 grams of protein per (cooked) cup; spinach has 5 grams of protein per (cooked) cup; a large stalk of broccoli has 7 grams; and one cup of raw, chopped kale has 2 grams. (For more information about which are the healthiest vegetables, click here.)

    Half a cup of cooked brown rice has 2.5 grams of protein; an ear of corn has 3 grams; and whole grain breads have a few grams of protein in each slice (check the label for specifics of particular loaves).

    Eating a variety of foods throughout the day, therefore, is likely to give you more than enough protein. "The only food category that really has none is fruit," says Largeman-Roth.

    7. Plant-based proteins come with fiber, vitamins, and antioxidants you won't find in animal-based proteins.

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    "You're actually getting a more complete nutritional picture with plant protein," says Largeman-Roth, "if they're coming from whole foods." Beans, nuts, and whole grains are also loaded with fiber and helpful micronutrients. Vegetables come with vitamins, phytochemicals, and other great stuff. But some animal-based proteins, like marbled beef and whole milk, go hand in hand with unhealthy fats. "Processed red meat commonly contains sodium, nitrates, phosphates and other food additives, and smoked and grilled meats also contain polycyclic aromatic hydrocarbons, all of which may contribute to the increased heart failure risk," said the lead scientist of a study published in an American Heart Association journal in June 2014.

    Largeman-Roth says chicken and fish are the best choices for animal protein, and when you have a hankering for red meat, steer yourself (see what I did there?) toward leaner cuts. She recommends including a mix of animal and plant-based proteins in your diet.

    8. Eating a variety of foods also limits your exposure to contaminants.

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    Even foods that are "good for you" usually come with some kind of nutritional downsides. "Variety is not just to be sure you're getting all of the amino acids, it's also to avoid contaminants," says Largeman-Roth. For example, in January 2014, Consumer Reports found that 97% of chicken — including some organic samples — harbor bacteria. Certain kinds of fish are high in mercury. Even some vegetables, depending on the variety and how they're grown, can absorb high levels of pesticides or environmental toxins. The bottom line: Eat lots of different kinds of food, and don't rely on any single one for your protein.

    9. Protein bars and shakes can be a good snack or between-meal supplement, but choose carefully.

    You shouldn't use protein bars to replace a meal, says Largeman-Roth, but some can be a good post-workout or between-meal snack. "What you want to look for first," she says, "is a real food as the number one ingredient." And that ingredient shouldn't be a sugar, even an organic one.

    Look for bars with 8 to 10 grams of protein, about 3 grams of fiber, and a "reasonable amount of sugar." What's reasonable depends on whether the sugar is processed versus coming from a natural source like dried fruit. A bar with dried fruit listed as the first or second ingredient should have less than 20 grams of sugar, she says, noting that many such products are not intended as protein bars. "For bars that do not include dried fruit as a main ingredient, there should be no more than about 5 to 7 grams of sugar per bar."

    The source of protein is also important. "Most is coming from soy protein isolate, which is a very broken-down form of soy I do not recommend my clients eating," Amy Shapiro, MS, RD, CDN, and founder of Real Nutrition NYC told BuzzFeed. Look instead for bars made with nuts or whole soybeans.

    Protein shakes, says Largeman-Roth "are not necessary, but can be useful for athletes who are refueling." But you need to choose carefully. In July 2010, Consumer Reports tested 15 protein powders and drinks, and found that several had levels of arsenic, cadmium, or lead exceeding levels considered safe. So do your homework before you buy your next powder!

    10. Eating tons of protein probably won't help you build tons of muscle.

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    There isn't a clear consensus about how much protein our bodies can use in a specific amount of time, but downing a lot at once isn't likely to help you build muscle.

    "Because the body can utilize only about 20 to 25 grams of protein at one dose, you won't build bigger muscles by eating a slab of beef for dinner or by downing a hefty protein shake for breakfast," writes sports nutritionist and author Nancy Clark.

    In addition, nutritionist Monica Reinagel points out in a broadcast for Scientific American that building muscle is only one way our bodies utilize protein, so consuming too much can backfire. "Protein, beyond what your body needs to replenish its amino acid pool or put to use for muscle building, is metabolized into glucose and used for energy," she writes. "And whenever you have more glucose than you need, the surplus is stored as fat."

    11. Eating too much protein probably isn't good for you.

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    Protein, like all food, has calories. So if you're eating extra protein but not cutting your carbs or fat, you're just eating extra calories, and that can translate into weight gain, a 2012 study at Pennington Biomedical Research Center found.

    High-protein diets can also exacerbate problems for people with kidney disease, according to a 2004 study. And other studies indicate that if you're not discriminating in the source of your proteins, and end up eating a lot of red meat, you might be at a greater risk of heart disease. "People who stay on [high-protein] diets very long may not get enough vitamins and minerals and face other potential health risks," says the American Heart Association. You can read more about these risks here.