4.A) The marketing is tempting: Get stronger muscles and healthier bodies with minimal effort by adding protein powder to your morning shake or juice drink. Or grab a protein bar at lunch or for a quick snack. Today, you can find protein supplements everywhere -- online or at the pharmacy, grocery store or health food store. They come in powders, pills and bars. With more than $12 billion in sales this year, the industry is booming and, according to the market research company, Grand View Research, is on track to sell billions more by 2025. But do we really need all this supplemental protein? It depends. There are pros, cons and some other things to consider.
B) For starters, protein is critical for every cell in our body. It helps build nails, hair, bones and muscles. It can also help you feel fuller longer than eating foods without protein. And, unlike nutrients that are found only in few foods, protein is present in all foods. "The typical American diet is a lot higher in protein than a lot of us think," says registered dietitian Angela Pipitone. "'It's in foods many of us expect, such as beef, chicken and other types of meat and dairy. But it's also in foods that may not come immediately to mind like vegetables, fruit, beans and grains."
C) The U.S. government 's recommended daily allowance (RDA) for the average adult is 50 to 60 gram of protein a day. This may sound like a lot, but Pipitone says: "We get bits of protein here and there and that really adds up throughout the day." Take, for example. breakfast. If you eat two eggs topped with a little bit of cheese and an orange on the side, you already have 22 grams of protein. Each egg gives you 7 grams, the cheese gives you about 6 grams and the orange -- about 2 grams. Add a lunch of chicken, rice and broccoli(西兰花), and you are already over the recommended 50 grams. "You can get enough protein and meet the RDA before you even get to dinner,"