The Unadulterated Truth About Protein (Protein Truths and Myths)
August 03, 2011 at 12:32 PM
The majority of Americans today are convinced that protein is the most important "thing" to eat and their "diet" must revolve around it ("diet" here meaning that which is consumed, ranging in purpose anywhere from a weight loss program to simply maintenance eating). Unfortunately, because of this belief and other misconceptions, consuming too much of the wrong type of protein has caused a less than optimal health state for many individuals. For yet others, it is a major contributing factor to developing chronic, debilitative disease states. Let us look first at the reality of what protein is, and, what it is not.
Protein is an essential human macronutrient, found in many food sources. Protein functions as antibodies, hormones, enzymes, as well as transport and structural components. Your body and its many organs, tissues, and cells use only the protein needed and excess is excreted through the kidneys. It is important to understand the following about protein:
- Protein is not "meat," which is essentially the muscle tissue of animals
- Protein derived from meat is not of higher quality than that from soy or a variety of other plants (1,2)
- Eating more protein will not make you stronger
- For athletes, eating protein from meat is not better than protein from plants (3)
- For all adults, infants, and children, protein from meat is not healthier than protein from plants (4)
- Protein does not give you energy (i.e. "I am tired today so I need more protein ...")
In fact, "energy" is derived most efficiently from carbohydrates; simple for more immediate, and complex for longer term energy. Complex carbohydrates are good carbohydrates and some of the very best nutrients to consume, contrary to what recent diet trends want you to believe (Atkins, South Beach, and The Zone). These carbohydrates are necessary nutrients, providing longer term energy, fiber, and due to being associated with unprocessed, whole foods, are accompanied by antioxidants, phytonutrients, and other micronutrients simply not found anywhere else in one's diet.
The World Health Organization and the Institute of Medicine believe the appropriate protein intake should be .5g to .75 g per kg body weight per day, while the American Heart Association, the National Cholesterol Education Program, and the American Cancer Society all recommend a diet where only 10% to 15% of calories are derived from protein. This translates into no more than 56 grams of protein for a 170 pound male adult and 48 grams for a 140 pound female. Most Americans easily consume two to three times this amount even though it is not needed. Those on a high protein-low carbohydrate diet can consume 5 or 6 times the required amount. So, what is the significance of this? There are two serious issues to be concerned with: 1) the demand this excessive protein places on the body and 2) the demand this false feeling of the need for protein places on our environment.
Protein's demand on the body:
As stated by the American Dietetic Association, high protein-low carbohydrate diets are "not recommended" and "potentially hazardous" (5). There have been literally hundreds of medical publications and numerous organizations arriving at the same conclusion that excessive protein, particularly animal protein, is unhealthy. Some of these organizations making a blanketed position statement against a high animal protein-low carbohydrate diet are the American Dietetic Association, American Heart Association, Cleveland Heart Clinic, Mayo Clinic, American Cancer Society, American Institute for Cancer Research, American Kidney Fund, World Cancer Research Fund, the Heat and Stroke Foundation of Canada, and the American Academy of Pediatrics. All of these organizations and many others call for "a diet based on a variety of plant foods, including grain products, vegetables, and fruits to reduce risk of major chronic diseases" (6, 7, 8, 9, 10). The reason is because high protein diets, particularly those of animal origin can cause the following health problems among others:
- Kidney failure. Consuming excessive amounts of animal protein puts an exaggerated strain and acid load on the kidneys. This load significantly increases the chance for stone formation, loss of calcium, dehydration, hyperfiltration, scarring, and chronic kidney disease. The source of the acid load is due to a) animal proteins are very high in sulfur containing amino acids (methionine) which creates acidity on oxidation to sulfate and b) severe restriction of carbohydrates cause production of keto-acids (11, 12, 13).
- Osteoporosis (bone loss), and kidney stones. Diets high in animal protein and low in carbohydrates are associated with negative calcium balance, bone loss, and exaggerated urinary stone risk factors such as hypercalciuria, low pH, and hypocitraturia. There are numerous studies showing that Americans with diets high in animal protein and even high in calcium derived from milk and cheese have lower bone density and higher risk of osteoporosis than vegetarians who do not consume dairy products and derive their calcium and protein from plant based sources. Dietary excesses of animal protein impairs calcium balance because the unused protein must be excreted which draws calcium out in the process. This is, in part, due to the high phosphorous levels and phosphorous to calcium imbalance that animal protein presents (14, 15, 16).
- Cancer. High protein diets in the form of animal products both red and white meat have been independently linked to cancer, increase the risk of developing cancer including colon, rectum, prostate, and breast cancer (17). The risk of cancer is significantly greater for those who eat meat of any type and who eat high levels of animal protein than for vegetarians who eat only plant based foods (18, 19). There are two reasons for this: First, meat has harmful, elements such as heme iron and heterocyclic amines which lead to cytotoxic factors causing cancer. Meat also contains saturated fat, cholesterol, and residual cancer chemicals from pesticides and herbicides. The Committee on Scientific and Regulatory Issues of the National Research Council analyzed oncogenic residues in food and found that there is a risk of consuming cancer causing pesticides and herbicides "in all meat, milk, and poultry products." (20). Second, protein can increase the risk of cancer because there is aÊlack of important cancer fighting nutrients in the diet of those eating high amounts of animal protein who avoid carbohydrate containing food. Plant based foods with complex carbohydrates contain fiber, minerals, vitamins, phytonutrients, and antioxidants. All of which are not found in animal products and all promote a stronger immune system and healthier organs and systems which reduce the risk of cancer.
- Coronary heart disease. High protein diets, particularly of animal origin, contain cholesterol, saturated fat, and other dietary factors which increase the risk for developing heart and other cardiovascular diseases. There is a higher risk from red meat and whole dairy products, however, there is still an increased risk for those consuming "lean" meat since all meat contains cholesterol, saturated fat, and other risk factors. Another issue is that the consumption of animal protein tends to increase blood levels of homocysteine which increases the risk of heart attacks. Additionally, high protein low carbohydrate diets create metabolic acidosis and an imbalance of calcium, magnesium, and potassium whereby, in a prolonged state of ketosis, cardiac arrhythmia or even cardiac arrest may occur (21, 22).
- Gout. Low carbohydrate diets increases blood uric acid concentration (hyperuricemia) increasing the risk or severity of the disease (23).
- Ketosis. High protein low carbohydrate diets can cause a metabolic state called ketosis where the body forms ketones which can cause organs to fail such as kidney and liver. Ketosis can be prevented by consuming at least 100 grams of carbohydrates a day (24).
- Nausea. High protein low carbohydrate diets cause constipation and nausea due to lack of fiber and ketone development (24).
- Halitosis. High protein diets and eating meat causes bad breath due to ketone development (25).
- Loss of energy. Contrary to what is commonly believed, individuals consuming high protein diets have less energy than normal because they are not eating carbohydrates which are the most efficient source of energy (26).
The American Institute for Cancer Research Diet and Health Guidelines call for "eating a variety of vegetables, fruits, whole grains and beans." These high-carbohydrate foods should push the protein and fat from animal sources to the side of your plate. Following a mostly plant-based diet and exercising regularly can help you slowly lose weight without undermining your health."
The burden high protein diets place on our environment:
The real cost of protein in the form of animal meat is not reflected in what is paid at the food store counter whether it is beef, pork, poultry, or fish. That is because the store price does not take into consideration all the resources, environmental change, and waste necessary for production of the meat. The destroyed forests and habitat, topsoil loss, billions of gallons of water consumed, fossil fuels used, unnecessary land use, and contribution to air and water pollution by the meat industry is immense. Seventy percent of all the grain produced and over 50% of our water consumption in America is used to feed animals which are then killed to be eaten. All of this is fueled by the false belief of Americans that high levels of protein from animals must be eaten. David Brubaker, at the Johns Hopkins School of Public Health, who studied our current food animal industry stated, "The way we breed animals for food is a threat to the planet. It pollutes our environment while consuming huge amounts of water, grain, petroleum, pesticides, and drugs. The results are disastrous." In addition to the 240 billion pounds of unsustainable sea creatures taken from the oceans each year for food, there are more than 57 billion pounds of sea life killed and discarded as unwanted by products including turtles and dolphins, estimates the United Nation's Food and Agriculture Organization.
For the past 30 years, hundreds of articles appearing in numerous medical and nutrition journals have concluded that protein in the form of animal meat is unhealthy. Despite this, very few Americans are aware of the facts or are not concerned and have not changed their eating habits. It is a great irony that the traditional plant based diet consumed by those in poorer, less developed countries supports a hard working lifestyle and is one that is relatively free of chronic diseases. In America and other developed countries, plant based diets are abandoned, replaced by meat, fat, and processed foods which causes a rise in obesity and many chronic diseases. The myth that we must consume large amounts of animal protein is driven by the meat and dairy industry and the large lobbying force they command. For instance, even when testimony was presented to eat less meat and dairy products when establishing the Dietary Goals for the United States in 1977, wording was changed in the document to skew reality and promote continued meat and milk sales due to the Committee receiving strong protests from the National Cattlemen's Association and the National Milk Producers Association (27). This, unfortunately, is what occurs frequently behind the scenes to keep America thinking that milk, meat, and high amounts of protein are necessary. This industry is then, responsible for our current inefficient use of land and other resources to produce food. Approximately 10 pounds of grain and soybean protein are fed to a cow for every one pound of meat produced. It takes 50 to 60 times more water to produce one pound of meat than it does to produce one pound of grain and vegetables. This is simply not an efficient way to produce food. Wouldn't it make more sense to grow crops and use water directly for human consumption? The drive for more protein in the form of meat combined with blatant inefficient use of our resources seems senseless considering there are 15 million children who die of starvation each year worldwide according to the World Hunger Organization.
An alarming 64% of all Americans are considered obese or overweight. This is because we are simply eating too many calories per day, and it is the wrong food being too high in animal protein and refined carbohydrates, saturated and trans fat. Diets high in animal protein increase the risk of a number of diseases including kidney, liver, coronary heart, gall and kidney stones, and cancer. High animal protein diets place an uneccessary burden on our environment. The myth of needing more protein is driven by the meat and dairy industry and certain cultural aspects.
The solution is to become more informed, eat less protein and more plant based foods. By doing so, you will do yourself and our environment a favor, and you will live healthier, longer and happier.
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