People who pay attention to nutrition news and trends inevitably hear about protein: Protein bars, shakes and powders, high-protein diets, counting protein grams, etc. But the fact is, most people who eat a healthy, varied and balanced diet do not need to worry about protein intake. A healthy eating plan provides more protein than required and less than the amount that can cause you trouble.
Protein's Thermic Effect
A diet high in protein with moderate or low carbohydrates speeds up your metabolism due to something referred to as the "thermic effect". Protein has the highest thermic effect of any food (nearly 30 percent). For example, if you eat 100 calories of chicken breast, 30 of those calories are burned off just to digest it! Therefore, the net caloric value is only 70 calories. Too much of any food will be stored as fat, but due to its high thermic effect, protein is less likely to be converted to fat than any other food type. When carbohydrates are reduced, the ratio of protein increases, and the thermic effect of the entire diet is higher.
Protein - a macronutrient found in everything from meat, eggs and milk to beans, nuts and even parsley is an important part of every cell in the body. Without it, there would be not only no health, but also no life. Protein is a key part of collagen in skin. It forms the oxygen-carrying hemoglobin in blood, the myosin that builds muscle, key hormones such as Adrenaline, insulin and growth hormone and many other substances.
Just as there are many types of fat, so too is there a wide range of proteins. In its latest updated report on daily nutrition, the National Academy of Sciences (NAS), noted that proteins in both the diet and body are more complex and variable than carbohydrates and fat. Also, protein-rich food is more likely than processed foods to provide key vitamins and trace elements, according to the NAS Dietary Reference Intakes Report.
The NAS report offers a formula for calculating the recommended dietary allowance. If you wish to do the math, it works out to 0.37 grams of protein for every pound of body weight for adults 19 years and older. Pregnant women need more - 0.5 grams of protein for every pound, plus an extra 25 grams per day. For those opting for a simpler method, the report sets 56 grams of protein as the recommended daily intake for men and 46 grams for women. The catch is that these numbers are based on a 154-pound man and a 127-pound woman.
Before you start obsessing about counting protein grams, know this: Large nutrition surveys conducted by the U.S. Department of Agriculture show that protein deficiency is rarely a problem in the United States. The exception: Some vegans, who eat no animal products.
What are some good sources of protein? The NAS report notes that protein from animal sources such as meat, poultry, fish, eggs, milk, cheese and yogurt provide all nine indispensable amino acids and for this reason are referred to as "complete" proteins.
Just three ounces of lean beef or poultry contain about 25 grams of protein - about half the daily allowance. Three ounces of fish or one cup of soy beans provide 20 grams of protein; one cup of beans is 15 grams of protein. Drink a glass of skim milk and get eight grams, or eat an egg or an ounce of cheese to get six grams of protein.
Some dense, whole-grain breads have up to five grams of protein per slice; cereals, grains, nuts and vegetables contain about two grams per serving. Parsley has one of the highest protein-to-calorie counts of almost any food - although you will have to eat mounds of parsley to get a significant amount of protein. A cup has 21 calories and provides about two grams of protein.
While supplements do provide protein, they do not necessarily mirror the type found in food sources and may come with extra saturated fat and with added minerals such as iron that in a chemical form is more difficult to absorb.
When possible, it is best to get protein and other vitamins and minerals from food.