How Much Protein Do We Need?
Protein is one of the essential nutrients we take in through our diets. How much protein a person should consume depends on several factors, including his age, weight and lifestyle. Despite the culture's current emphasis on protein, many doctors believe Americans eat far more protein than they need. And, since all proteins are not equal, there's evidence to suggest that what kinds of protein we consume is at least as important as how much. Another consideration is what percent of total caloric intake comes from protein.
Importance of Protein
Protein is what muscles and ligaments are made from, but it's also vital for our immune, circulatory and respiratory systems. Amino acids, which make up proteins, serve important functions within individual cells, too, not the least of which is translating the information stored in DNA. Too little protein will eventually cause death, but too much can strain the liver and kidneys. There are about 20 different amino acids, some that are made in our bodies and some that must come from our diets.
Maintenance
The U.S. Department of Agriculture's recommended daily intake of protein is 0.4g per pound of ideal body weight. To calculate this, take your ideal body weight (determined by height and body type), divide it in half and subtract 10. For example, if your ideal body weight is 180 pounds, you should consume about 80g of protein per day. At 120 pounds, you should consume 50g of protein per day. Chances are, if you aren't a vegetarian and eat a wide variety of foods, you regularly exceed this daily intake level. However, the figure should be regarded as a rough estimate: Elderly people and lactating women will need a bit more protein.
Physical Activity
Your level of physical activity will also have an impact on your nutritional needs. Athletes and bodybuilders intentionally exceed the daily recommended allowance of protein by significant amounts. Someone trying to put on muscle can eat 1 to 1.5g of protein per pound--two to three times the recommended amount. A bodybuilder who weighs 160 pounds can consume 160 to 240g of protein per day. No wonder body builders drink high protein drinks to supplement their intake. Divided over six meals, this is still 26 to 40g per meal--and many bodybuilders, of course, weigh more than 160 pounds.
Protein Sources
No matter what your total level of daily protein intake, the matter of where you get those grams of protein cannot be avoided, especially if you're a vegetarian or vegan. To function properly, the body needs all the amino acids, and having too few of one type cannot be compensated for by eating more of another. Animal-based foods such as meat, fish, and dairy products are called complete proteins because they contain all the essential amino acids. But they are usually high in saturated fat, and this carries its own risks. Most plant-based foods have only incomplete proteins, meaning they need to be combined with another kind of food to include all the amino acids. Quinoa, a South American grain, is one of the few complete plant proteins.
Caloric Intake
Doctors generally agree that protein should make up 10 to 20 percent of your total caloric intake. Bodybuilders would probably be on the upper end of that scale, while more sedentary individuals would be on the lower end. For a 2,000 calorie daily diet, this translates to 200 to 400 calories per day from protein. Since protein has 4 calories per gram, this means 50 to 100 grams of protein per day for a 2,000 calorie diet.
Tags: amino acids, body weight, ideal body, ideal body weight, should consume