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Without a doubt, protein is the most highly respected of all the major nutrients. Named after the Greek word proteios, which means “of prime importance,” protein plays a more varied role in the body than either carbohydrates or fats. This powerhouse nutrient supplies the building blocks needed for the growth and repair of body tissues. In fact, it’s part of every single cell and makes up the body’s structural elements like the skin, nails, muscles, teeth, bones, and organs. But its benefits don’t stop there. Protein provides enzymes and key hormones, enables nerve and brain cells to effectively communicate with one another, and helps the body resist disease by regulating antibodies. It also moves needed nutrients into and out of your cells and around your body. Bottom line: Without protein, life would cease to exist.
But, for all its importance, protein is one of the most misunderstood nutrients we eat. What’s the best type of protein? How much is too much? And how can you tell if your body is absorbing the protein you do eat?
Quality and Quantity
The protein you eat doesn’t go directly into your skin, bones, and muscles. Instead, it is broken down into amino acids that the body uses to build the specific proteins it needs. This process begins in the stomach, where digestive enzymes like pepsin break the protein strands into smaller pieces called peptides. When these peptides move into the small intestine, other enzymes from the pancreas and small intestine deconstruct them into amino acids that can be readily absorbed into the bloodstream.
Because the body can’t store these amino acids, it’s important to include protein with every meal. How much total protein should you eat? The amount needed in a person’s daily diet is determined by their body weight, body composition (fat to muscle ratio), level of activity, and the type of physical activity they engage in. While the ideal amount of protein varies from person to person, current recommendations state that a healthy adult needs 0.8 grams of protein per kilogram (or 2.2 pounds) of desirable body weight. This works out to about 46 grams of protein per day for women and 56 grams for men to prevent a deficiency. But keep in mind, these recommendations are for a relatively sedentary person and they don’t reflect optimum amounts. Active folks and athletes need considerably more protein—between 1.2 to 1.8 grams per day for each kilogram of body weight.
See also 5 Benefits of BCAAs
But it’s not just the amount of protein you eat that matters, it’s also the type of protein you consume. Complete protein, like that found in lean meats, fish, poultry, eggs, dairy products, and soy, provides ample amounts of all nine of the essential amino acids. Complete protein is also the most easily absorbed. Incomplete proteins, like those in beans, legumes, grains, and other plant foods, contain limited amino acids and are not absorbed as well as complete protein. Fortunately, eating a variety of complete and incomplete proteins each day can give your body all of the essential amino acids it needs. You can also combine two or more incomplete proteins—such as navy bean soup and whole grain bread, lentil curry and brown rice, or even peanut butter on whole wheat toast—to form a complete protein.
Boost Your Absorption
It’s hard to imagine that anyone in America suffers from a protein deficiency, yet it’s estimated that one-third of people over age 60 don’t get enough. Vegetarians and crash dieters can also run the risk of insufficient amounts. Signs of a protein deficiency include hair loss and brittle nails, extreme fatigue, constipation, diarrhea, and unexplained weight loss. But getting enough protein is more than just a numbers game—its also about absorption.
Protein is most readily absorbed in an acidic environment. This means you need to have sufficient stomach acid to uncoil the protein strands so that the digestive enzymes can break them down into smaller molecules. You can enhance this process with supplemental digestive enzymes. Because your body’s enzyme production drops off after you hit age 30, it’s smart to add an enzyme supplement that specifically targets protein digestion. Known as proteolytic enzymes, these include papain from papaya, and bromelain from pineapple stems. You can find these supplemental enzymes as either stand-alone supplements or as part of some supplemental protein powders. If you opt for a separate enzyme supplement, make sure to take it with food for best results.
Should You Supplement?
If you are looking to lose weight and/or build muscle, pumping up your protein intake can be a smart move. Adding protein powders and bars to your diet can provide both convenience and a concentrated source of this vital nutrient. But, with so many products on the market, how do you choose? Protein supplements are typically made from egg whites, milk (casein or whey), or soy. Don’t eat meat or dairy? You can also find vegan sources from hemp seed, rice, or pea protein.
When trying to decipher the labels on supplemental protein products, it’s a good idea to understand the lingo. Protein concentrate is the least expensive type of protein. It often contains more fat and carbohydrates and can be clumpy and hard to mix. Protein isolate contains lower amounts of fat and carbs. It’s easy to mix with liquid and is well absorbed by the body. Hydrolyzed protein is usually a whey protein that has had some of its amino acid peptide bonds broken down into smaller molecules that are readiy absorbed by the body. Hydrolyzed protein is often combined with protein isolates for an effective and tasty way to power up.
Digestive enzymes that target protein digestion, known as proteolytic enzymes, include papain from papaya and bromelain from pineapple.
Green + Protein
Green foods, like spirulina, barley grass, chlorella, and wheat grass, are super-concentrated sources of nutrition, and often-overlooked sources of protein. Now some companies, like Paradise Herbs and Vibrant Health, are combining green foods powders with soy, rice, or pea proteins for a super-nutritious protein powder blends, especially great for vegetarians and vegans. “Spirulina is a tremendously rich source of protein,” says Aimee E. Raupp, MS, LAc, author of Chill Out and Get Healthy. “It is full of age-fighting antioxidants, boosts your immune system, and in a nutshell, is amazing for your overall health.”
Fact & Fiction
Even though protein is critical to good health, it’s become quite controversial. The popularity of the high-protein weight- loss diet has spawned a number of myths and half-truths about consuming large amounts. Here’s the real scoop:
Consuming large amounts of protein causes osteoporosis. Although some early studies appeared to show that higher protein intake caused an excretion of calcium (which would ultimately lead to bone loss), recent data not only debunks this myth, it shows that protein may actually prevent bone loss. Even though eating less protein results in less calcium being excreted by the body, it also reduces calcium absorption. The net effect is a decrease in calcium levels.
See also 7 New Ways to Use Protein Powders
Too much protein is bad for your heart. According to Harvard School of Public Health, replacing carbohydrates with protein may decrease the risk of blocked arteries, a condition known as atherosclerosis. Trading in some of your carbs for lean animal or vegetable protein also improves your lipid profile by lowering triglycerides and boosting HDL (good) cholesterol levels. However, eating large amounts of protein-rich food high in saturated fat—bacon, T-bone steaks, cheese and whole milk—can wipe out these heart-healthy benefits.
High protein diets can lead to weight loss. This is one “myth” that has merit. Scientists from the University of Illinois report that, even though combining exercise with either a high-carbohydrate or a high-protein diet can lead to weight loss, the biggest losers appear to be those on a high-protein diet. Opting for lean animal or vegetable protein over other types of foods increases saiety, boosts the body’s abiltiy to burn fat, and enhances energy efficiency.
Eating a lot of protein is bad for your kidneys. Most studies that came to this conclusion were conducted on people with existing renal problems. Based on more recent evidence showing that a high-protein diet doesn’t put any stress on the kidneys, the International Society of Sports Nutrition concluded that concerns about the safety of high protein intake is unfounded in healthy, exercising individuals