Much of our body, including muscles, organs, skin, hair, and enzymes is made primarily of protein.
Protein is in every cell and is necessary for life. Protein, in turn, is composed of amino acids. Some amino acids are manufactured by the body. Nine others called essential amino acids must come from the foods we eat.
Our bodies need a constant supply of protein. We don’t store it as we do fats. However, getting enough protein isn’t a problem for the vast majority of people. Most of us, in fact, get too much protein in our diets, or at least more than we need. The average woman eats 65 grams of protein daily; the average man eats 90 grams a day. Some high-protein diets recommend double or even triple that amount.
In 2002, the National Academy of Sciences published a new Dietary Reference Intake on everything from fiber to fatty acids. They recommend that, in order to reduce the risk of developing chronic degenerative diseases, an optimal range of protein intake is 10 to 35 percent of calories. (On a 2,000-calorie-a-day diet, this would be 50 to 175 grams of protein.)
How Much Protein Do You Need?
- Adult women – at least 46 grams of protein
- Adult men – 56 grams
- Very active and elderly people – somewhat more than 56 grams
Easy Ways to Get Protein
- 3 ounces of tuna (20 grams of protein)
- 3 ounces of turkey breast (26 grams of protein)
- A slice of whole wheat bread has about 3 grams of protein
- An ounce of almonds as 6 grams
Since many foods contain protein (a cup of lentil soup has about 7.8 grams; an egg, 6 grams; and a baked potato, 3 grams), you can see how quickly most people would reach their protein goal on a daily basis.
What About High Protein Diets?
Many people mistakenly believe that there’s some special “fat burning” paradise that you enter when you severely restrict your carbohydrate intake and simultaneously boost your protein intake. There is nothing magical about a high-protein diet, despite our eagerness to believe so. The simple, irrefutable fact is that if you eat more calories than you burn, you’ll gain weight; if you burn more than you consume, you’ll lose. Most people who follow a high-protein diet and lose weight do so simply because their food choices are such that they automatically cut down on calories. When you restrict or severely limit one group of foods (carbohydrates), a group that ordinarily comprises over half your calorie intake, you can’t help but lose weight. And once you go off the diet, all or most of the weight usually comes back.
There are a few proven dangers in an exceptionally high protein intake. For one thing, the more protein you take in, the more calcium you excrete in your urine, thus raising your risk for osteoporosis. In the Nurses’ Health Study, women consuming more than 95 grams of protein a day (an extra-lean 6-ounce hamburger has 48.6 grams of protein) had an increased risk of fractures. While there is ongoing debate on this subject, it seems that vegetable protein causes less bone loss than animal protein.
A high-protein diet is also associated with some risk for kidney damage among susceptible people. If you have below-normal renal function, you should talk to your health care professional prior to trying a high protein diet.
Another danger of excessive protein in the diet has to do with insulin levels. One of the arguments for a high-protein diet is a claim that too many carbs raise the blood insulin level, which in turn causes weight gain by forcing the calories into fat cells rather than allowing these same calories to be burned as energy. A Michigan State University study seems to disprove this argument. In reality, higher insulin levels are a risk factor for developing diabetes and perhaps cancer.
It’s easy to consume sufficient protein if you re a vegetarian. If you select from two or more of these three groups in a given day, you’re set:
- Whole grains
- Nuts and seeds
Unfortunately, for most people in the United States, a high-protein diet means an increase in their consumption of red meat. It’s this type of protein—with its associated saturated fat—along with the increased and disproportionate amount of it, that has the greatest negative impact on long-term health.
There is wide consensus that it is prudent to keep one’s intake of saturated fat less than 7 percent of fat calories. Two significant sources of saturated fat in the typical American diet are red meat and full-fat dairy products. Numerous studies suggest there is a relationship between increased dietary saturated fat and colon cancer, coronary heart disease, and Alzheimer’s disease. In addition, a number of studies have shown a link between red meat consumption and prostate cancer. It is also important to remember that saturated fat intake has a much stronger influence on increasing serum cholesterol than does dietary cholesterol intake. Substituting skinless turkey breast for higher-saturated-fat protein choices is an easy strategy to help lengthen your health span.