Factors affecting daily protein requirements
The amount of protein you need each day can vary based on several factors, including age, gender, genetics, health and the quality of the protein. For this reason, guidelines are general to help you get an idea of how much protein you need.
By body weight
One way to define protein needs, is to say that every day we need about 7 grams of protein for every 20 pounds of body weight. This means that if you weigh 150 pounds, you would need about 52.5 grams of protein each day.
150 ÷ 20 = 7.5 7.5grams x 7 = 52.5grams
Many healthy eating experts put it a different way by saying that we should get about 30% of our calories each day from healthy eating protein sources. Protein has about 4 calories per gram, so if you consume 2400 calories a day, about 720 of them should be from protein.
2400 calories x 30% = 720 calories
Using the Pyramid to focus on daily protein requirements
Another way of defining protein needs is in reference to the Food Guide Pyramid, which is a way to visualize the amount of food you should eat from each of the five food groups, each day. By this method, depending on your weight, you need two to three 3-ounce servings of meat, fish, poultry or meat analog each day. (A meat analog is a soy or grain based product that is manufactured to look and taste like certain meat products.)
Recently, the USDA introduced a new concept called simply "My Plate," a visual representation of the variety of foods that should regularly be found on our dinner plates, including protein foods.
You are probably meeting your daily protein requirements
If you are not a mathematician, but a gourmand, and you don't want to sit around doing equations to find out what you should eat. Suffice it to say, that if you live in a developed part of the world such as Europe and the U.S., it is more likely that you are getting too much protein than not enough.
When you consider that most foods have some protein and many foods are a significant source of protein, if you are eating three healthy meals a day, you are likely getting enough protein.
If you have eggs (possibly with sausage or bacon) or cereal with milk or toast with peanut butter for breakfast, a salad with chicken breast or a ham and cheese sandwich or minestrone soup for lunch, and a hamburger or a pork chop or spaghetti and meatballs for dinner, you are most likely getting more than enough protein. Even if you missed one of those meals, you probably are still getting enough protein.
However, if you live in an underdeveloped country, severe protein deficiency could be a real concern. People in poor countries often struggle to meet the minimum daily protein requirements.
What does a serving of protein look like?
If you don't have a scale to weigh your meat, one guideline for visualizing a serving of meat is that the portion should be the size of a standard deck of playing cards. (Just imagine how many servings are represented by that prime rib served at your favorite restaurant--enough for the whole family!)
For protein sources that do not come from meat, a serving, which is 1 large egg, 1/2 cup cooked beans or rice, or 2 Tablespoons of seeds, nuts or peanut butter, is equivalent to only about 1/3 of the protein in a serving of meat. Tofu is also in this group with a serving size of about 4oz.
In addition, most nutrition experts recommend that, whenever possible, choose a leaner or low-fat version of the significant protein sources.
Another aspect of daily protein requirement, is that foods that contain all of the essential amino acids are called “complete proteins.” These complete protein foods are generally animal foods. Plant foods do not, as a rule, have complete proteins, but by combining certain plant foods, called “complementary proteins, ” you can make a complete protein.
For example, when you eat Granola with milk, you are obtaining a complete protein. The grains, seeds and dairy complement each other, in that each has some of the essential amino acids and when eaten together, they provide all of the essential amino acids.
It's generally believed by food scientists that it is not necessary to eat these complementary proteins at the same meal.
Click here for a list of complementary proteins.
Rule of thumb
Complete Proteins = Animal proteins
Incomplete Proteins = Plant Proteins
You already know that protein is necessary for good health. For that reason, if you do not get your daily protein requirement, it will have a noticeable effect on your health, from making you more susceptible to infections to causing you to literally waste away.
In developed countries, severe protein deficiency is prevalent among those in extreme poverty or those suffering with eating disorders, such as anorexia nervosa. Severe protein deficiency can be fatal.
What happens if I exceed my daily protein requirements?
As with anything, you can get too much of a good thing. If you eat too much protein, your body can convert it to energy, and if that energy is not used, it will be stored as fat, which could lead to obesity.
In addition, eating excessive protein puts a heavy load on your kidneys which must get rid of the by-products of protein metabolism. There has also been some suggestion of a link between eating large amounts of animal protein (which is usually accompanied by saturated fat), and heart disease, cancer and possibly diabetes.
General protein recommendations
Eat some protein foods as part of each meal. Eat protein from a variety of sources. In the case of animal protein, concentrate on the leaner or low-fat types.
Just for fun, investigate some of the plant protein foods, such as nuts, seeds and legumes that you can add to your healthy eating lifestyle plans.