I call this the dreaded question not because I don't have an answer to it (in fact I have scads of answers and supporting data, which I will tell you about), but because it provides a little glimpse into the misconceptions that most people have about what constitutes correct nutrition.
You see, in America and throughout the industrialized world, we have a significant misunderstanding of protein, what it does and its possible dangers. That's right, I said dangers. If you are nutritionally naive and are reading this, you probably have never been told that protein is potentially dangerous. If you are like most of us, you have been taught that protein is good for you, and the more the better. You may even believe that foods are not good for you if they don't contain enough protein. Finally, you might even think that the only way to get enough of the "right kind" of protein is to eat meat. Sadly, this is at best a distortion of the truth, and at worst, a baldfaced lie. Worst of all, the lie is perpetuated by the people who produce the meat, to the expense of our national health.
The protein myth began innocently enough. At the turn of the 20th century, we finally had enough of a working knowledge of organic and biochemistry to begin analyzing the contents of the food we ate. It didn't take very long for food scientists to figure out that the food we eat is composed of three macronutrients: carbohydrates, fat, and protein. By experimenting on animals, it also didn't take long for them to figure out that if you deprive an animal of protein completely, it dies before too long. This was not so of carbohydrates or fat (in truth, it is a little more complex than what I write here, but the gist is the same). Thus, the scientists correctly concluded that protein was absolutely necessary for life. Even its name, protein, is from the latin proteus, meaning "first."
To this point the scientists were absolutely correct. In fact, if a human being does not get enough protein, they develop a malnutrition condition called kwashiorkor, which eventually leads to death. Protein is important, and that fact became widely known among laypeople. No problem there. Unfortunately, this is where the train began to go down the wrong track. Scientists, wanting to completely understand protein, began to experiment to define how much is enough. Most of there experiments were done on rats, and they settled on a "dose" of 1 gram per kilogram of body weight. What they did not realize at the time is that not all animals had the same protein requirements, and rats happen to require far more protein than humans do.
The problem only got worse from here. Of course, if some is good, more is better, right? Thus, we began to eat more and more protein, usually in the form of animal flesh (meat), since it was the "perfect protein" as it provides all the amino acids in once source. In fact, scientists define the "quality" of a protein by two factors: how easy it is to digest, and how many of the 20 amino acids it supplies. This led to a vast increase in protein intake, from about 10% of our daily calories to about 45% or so today.
You can imagine that the people who produce the meat are rather happy about this, and do everything they can to promote the virtues of protein. Most people in our culture are educated (read: brainwashed) to believe that if you do not eat meat with virtually every meal, you are sickly and weak, and cannot build muscle or do anything athletic.
So what, you might ask. Why is protein so bad anyway? The answer is, it's not, if eaten in the right amount, from the right sources. Here are some myths about protein:
1. The more protein, the better: This is not only false, but potentially deadly. In fact, the human body only needs about 10-15% of its daily calories from protein. This is enough for the body to repair the tissues of its organs, and to build new muscle and connective tissue as needed. More than this, however, can be quite detrimental, for two main reasons. First, the more protein you eat, the less carbohydrates and fat you eat. These nutrients are also important for a variety of body functions, and the micronutrients (such as vitamins, phytochemicals, and fiber) which go along with the carbohydrates in plant foods are lost when you eat a meat heavy diet. Second, protein is composed of amino acids. When you eat a large amount of protein, your body takes on a huge acid load, which it must then deal with. Since the body operates at a slightly alkaline pH, it must buffer this acid load. It has two ways to buffer. The weaker of the two is to shift acid back and forth between the lungs and the kidneys. The stronger of the two is to dissolve your bones, freeing up phosphorous to bind up the extra acid. Thus, a heavy protein load is hard on the kidneys, and many doctors now think that the high rate of osteoporosis in America and other industrialized countries is related to our massive protein intake.
2. Meat is the best source of protein: The main reason that food scientists originally thought this was due to what are called essential amino acids. You see, your body can make 12 of the 20 amino acids that you need from scratch. We are unable, however, to manufacture the other 8. These must be obtained from the diet. For the early food scientists, meat seemed like an optimal protein source because it contains all 20 amino acids. No vegetable protein source other than soy has all 20. This would be a really big deal if it made the slightest difference practically. In reality, however, it is not important to have all 20 amino acids together. In fact, you don't even need to take in all 20 from your diet. You only need 8 of them, remember? Thus, as long as you get enough of those 8 amino acids, your body has everything it needs to repair old tissues and build new ones. Whether you are a world class body builder or an infant, that is all the protein you need. Taking in more does not make you build more muscle, it just damages your kidneys and bones. Therefore, vegetables are a perfectly good protein source, and meat is in no way necessary for health or life. Eating meat also comes with some inherent dangers, such as cholesterol intake, as well as significantly higher rates of hypertension, heart disease, cancer (multiple types), osteoporosis, depression, heart attack, stroke, and premature death.
3. Athletes need more protein than non athletes: If you are an athlete, this will come as a complete shock to you, but your protein requirements (amount and type) are no more than anyone else's. All you need to eat is enough of the essential amino acids (10-15% of daily calories), and your body can build all the muscle you need. If you don't believe me, just ask Mac Danzig. He is a vegan MMA fighter. If anyone needs to build a lot of muscle, it is him, but he manages to do it on an all plant diet.
4. Chicken and fish are better than beef: In a wonderful bit of animal product in fighting, the chicken people try to convince you that their product is better than the evil beef, which is loaded with fat, and will kill you. That is true, but it is also true of chicken. Chicken may be slightly lower in fat, but as we have discussed, it is not necessarily the fat which is dangerous in animal products. Chicken still gives you the same excessive protein load, with no redeeming vitamins, minerals, phytochemicals, or fiber, all of which you get when you eat plant based proteins.
5. Plant foods don't have enough protein in them: This is the final argument of the animal producers. You have to eat meat, to supplement (or replace) plants, because they don't have enough protein. Excellent propaganda, but completely not true. Let's take the much maligned potato for example. The potato, which is often decried for being a starchy carb bomb, and having little health value, has quite a bit of protein. Depending on the type of potato, it can have anywhere between 8 and 11% protein by weight. Interestingly, this is just about the amount that you need. Potatoes do not have all of the essential amino acids, so you could not survive on a diet of just potatoes, but you get the point. A diet consisting of a variety of vegetables can easily provide enough protein for good health and muscle development.
By now, you might wonder what my answer is when I am asked the dreaded question. Obviously, I don't carry around a pamphlet with all this information on it, to pass out on demand (although maybe I should). Depending on how much time I have, I either give the short and slightly snarky answer- from food, or the answer which leads to a long discussion- why do you think that protein is so important? Hopefully you will ask yourself that question the next time you sit down to a steak or some chicken.
M. Jacob Ott, M. D.
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