On this segment of “Take It Off Today,” we look at protein. What is it? And why does our body need it? Madelyn Fernstrom, a “Today” contributor and director of the Weight Management Center at the University of Pittsburgh Medical Center, was invited on the show to share some basic information about proteins.
Until the craze of high-protein diets a few years ago, most dieters didn’t pay a lot of attention to their protein intake. But everyone needs protein for their bodies to function. Protein is one of the big three macronutrients. The other two are carbohydrate and fat. Adequate protein intake is essential for good health: It’s necessary for maintaining the body’s normal growth and its muscle mass (which is mostly protein), its immune system, and heart and respiratory functions.
Protein deficiency is generally not a problem in the U.S., but it is in many parts of the world. Malnutrition takes two forms: a person doesn’t get enough total calories (and they waste away) or he doesn’t get enough protein. Chronic protein deficiency can result in death (this is one of the dangers of anorexia).
How much protein do you need for good health?
As a general rule, between 10 percent and 15 percent of your total calories should come from protein. So, if you consume 2,000 calories per day, at least 200 should come from protein, or about 50 grams. You should try to eat around one gram of protein per one kilogram of body weight, or around 0.4 grams per pound. An easier way to figure this out in your head is to take your weight, divide it in half, and subtract 10. The total will be the number of grams of protein you should consume each day. So, if you weigh 120 pounds, you should eat about 50 grams of protein.
Can you get too much protein?
Not really. The only danger is if you have liver or kidney disease. That’s because these organs are your body’s “workhorses” that metabolize protein. So, if you have kidney or liver disease, such as cirrhosis or fatty liver, talk to your doctor.
What is protein?
Amino acids are the building blocks of protein. Think of a train as a protein and the cars as amino acids. The combination of amino acids determines the type of protein. There are two types of protein: animal and plant. However, there are about 20 amino acids, divided between essential amino acids and non-essential ones. Essential means the body cannot make them and must obtain them from a food source. Your body can break down essential amino acids into non-essential ones.
How many amino acids do you need?
Your body needs all the amino acids. Depending on amino acid composition, proteins are either “complete” or “incomplete.” This is the real difference between the vegetable and animal protein sources. Animal protein has the complete profile of all the amino acids. Beef, chicken, veal, lamb, port, fish, eggs, are all complete proteins. Eggs are the most ideal protein — and the standard to which others are measured regarding “usability” by the body.
Vegetable proteins are typically “incomplete,” meaning there are either missing amino acids or too few of them to maintain the body’s total needs. Vegetable proteins come from nuts, seeds, and legumes. Vegetable proteins need to be combined, but not necessarily eaten together, to make sure all amino acid needs are met. Vegetarians must use “complementary” vegetable proteins together to make a single complete protein source. For example, they need to eat beans with rice, a rice cake with peanut butter, or hummus, which is made with chick peas and sesame paste. Soy is a great low fat source of protein. Most protein bars use soy protein, casein or whey as their base. All are complete proteins. The same is true for protein powders.
You don’t have to get all your amino acids every day. Children should try to get as complete an assortment of amino acids as they can on a weekly basis. Adults should aim to get all their amino acids on a monthly basis. We do have a biological drive to seek protein to satisfy our bodies’ needs, so there is little likelihood we will have deficiencies. But balance is key.
Many people find protein more satisfying ounce per ounce than carbohydrates, so you can easily eat more protein than you need to be healthy. The recommended daily amount is two or three (4-ounce) servings. For concentrated proteins like meat, a serving is the size of a computer mouse. But watch the fat content. Many animal proteins contain fat. So choose lean meats and non-fat dairy products to limit your fat intake. And don’t eliminate carbohydrates and fat — this imbalance can damage your health.