For some of us who have diabetes, the trouble with protein is real. If we have existing kidney disease, we can’t handle a lot of protein. If we follow a vegan diet, the problem is to get enough protein.
But for most of us, the trouble with protein is to know how much we need and whether we are getting too much. Many of us think that when we go on a very low-carb diet, we have to boost the amount of protein we eat.
It’s not enough to know just about calories and about two of the macronutrients, carbohydrates and fats. The third macronutrient, protein, often gets too little attention in our personal knowledge base.
Protein is an important component of every cell in our bodies. Our bodies use it to build and repair tissues and to make enzymes, hormones, and other body chemicals. Protein is an important building block of our bones, muscles, cartilage, skin, and blood. Unlike fat and carbohydrates, our bodies don’t store protein, so we regularly need to refill our personal tanks.
Finding the answer to the question of how much we need every day is actually pretty easy. The key measure is the Dietary Reference Intake, a system of nutrition recommendations from the Institute of Medicine of the U.S. National Academy of Sciences. Used by both the United States and Canada, the DRI supersedes the Recommended Dietary Allowances (RDAs), which is nevertheless still used in food labeling.
Like other men, I need just 56 grams of complete protein per day, according to the Food and Nutrition Board of the Institute of Medicine. Most adult women need 46 grams. Pregnant women and nursing mothers need 71 grams.
The Food and Nutrition Board defines complete protein this way: “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 protein.’”
Most people accept these amounts, since this respected organization shows in such detail how they reached their conclusions. But then, of course, the problem is for us to put them into practice. This is most important for vegans and probably for many vegetarians. It means having to weigh what we eat and count the grams of protein. If our diet doesn’t change a lot from day to day, this can be a lot easier in practice than in sounds, since we only need to establish a personal baseline.
Perhaps even more important for most people is to know how much protein is too much. But this is a lot harder to determine than finding out our minimum needs. One of the complications is that protein consists of 20 amino acids, of which nine are essential—in other words, which our bodies need to get from our food. The Institute of Medicine has set what it calls the Tolerable Upper Intake Level (UL), but only for vitamins and not for any of the macronutrients.
Some people are concerned about high-protein diets. The main reason why I went to the American Diabetes Association meeting in San Francisco five years ago was to listen to the “Great Protein Debate.” But except for people who have existing kidney disease, researchers have found “no significant evidence for a detrimental effect of high protein intakes on kidney function in healthy persons after centuries of a high protein Western diet.”
Now, more people than ever are eating a high protein diet. Some of them are people who are eating a very low-carb diet to manage their blood sugar level as well as their weight. While a low-carb diet implies a high-fat diet rather than a high-protein diet, some people are finding that increasing their protein intake satisfies their hunger better than either high-carb or high-fat foods do. One of my early articles about diabetes, “What Really Satisfies,” which I wrote for Diabetes Interview in 1998, shows that protein-rich foods are some of the most satisfying.
Although eating more protein can help us lose weight, we do not have to increase how much protein we eat when we go on a very low-carb diet. But we usually do need to increase the amount of fat in our diet, because only fat can provide the immediate energy we need when we cut back on carbs.
This article is based on an earlier version of my article published by HealthCentral.