Protein and Calcium Myths
People are increasingly concerned about adopting healthier diets. However, many are prevented from necessary changes because of myths about certain nutrients. For example, it is the common wisdom that one should eat ample amounts of meat in order to get adequate protein and large amounts of dairy products in order to get adequate calcium to avoid osteoporosis.
But, please consider the following: Countries with the highest consumption of dairy products, such as the United States, Sweden, Finland, and Israel also have the greatest incidence of female osteoporosis. Eskimos, who consume the highest amounts of calcium of any of the world’s people, have the highest number of cases of osteoporosis. Osteoporosis occurs relatively infrequently in China, where most residents are lactose intolerant, and consume very little milk or other dairy products.
The reason is that people on meat- and dairy- based diets are getting far too much protein, generally 2 to 3 times the amount required, and when the excess protein is excreted, calcium and other minerals are drained from the body. A recent study showed that people getting 1400 milligrams per day of calcium along with about 150 grams of protein had a negative calcium balance of 65 units while people getting only 400 milligrams of calcium per day with only 50 grams of protein had a positive calcium balance of 31 units.
The main problem is the consumption of animal protein; studies have shown that protein from non-animal sources has health benefits. So the answer to preventing osteoporosis is not to consume a lot of dairy products, but to reduce animal protein consumption through a balanced, nutritious diet centered on the “New Four Food Groups”: fruits, vegetables (especially broccoli, a very calcium-rich food, without the negatives of animal products), grains, and legumes.
Researchers have found that the consumption of high-fat dairy products is a leading cause of atherosclerosis, heart attacks, and strokes. While lower-fat dairy products represent an improvement, they are higher in protein, and this contributes to osteoporosis, kidney problems, and some forms of cancer. Dairy products are also the leading culprits in food allergies. Actually, milk is a wonderful product, but it was designed for rapid weight gain in calves. One might wonder if drinking milk is natural to human beings when we recognize that no other mammal on earth consumes the milk of another species or consumes it after a weaning period.
Many plant foods are good sources of calcium. Especially good sources are dark leafy greens (such as kale and mustard, collard, and turnip greens), broccoli, beans, dried figs, sunflower seeds, and calcium-fortified cereals and juices. Dairy products are good sources of calcium, but they also contain large amounts of fat and protein.
According to an American Dietary Association paper, vegans (who consume no animal products at all) can obtain the calcium they need from plant foods alone, and studies have shown that vegetarians can absorb and retain more calcium from foods and have lower rates of osteoporosis than non-vegetarians.
The question most frequently asked of vegetarians is “How do you get enough protein?” However, the amount of protein that a person needs (as a percent of total calories) is actually relatively low: 4.5%, according to the World Health Organization of the United Nations, 6%, according to the Food and Nutrition Board of the U. S. Department of Agriculture, and 8%, according to the U. S. National Research Council. It is extremely significant that during infancy, the period when humans have the most rapid growth, mother’s breast milk provides only 5% of its calories as protein.
Adequate protein can easily be obtained from vegetarian, even vegan (no animal products at all) diets. Protein is found in most plant foods as well as in animal foods. Potatoes, for example have 11% of their calories from protein, and spinach has 49%.
While an average working man needs about 37 grams of protein per day. 3,000 calories of rice alone would provide 60 grams of highly usable protein (for 3,000 calories of potatoes, 80 grams of protein would be provided). It is almost impossible not to get adequate protein, even on a plant-based diet, providing that one is getting enough calories and consumes a reasonable variety of foods. If this is true, how is it that we have gone so far wrong and so many people think that getting sufficient protein is a major dietary concern. The reason is that much of our nutrition information has come from experiments on rats, and rats require far more protein than humans do, as seen from the fact that a rat mother’s milk has almost 50% of its calories from protein.
Consuming excessive amounts of protein can seriously damage human health. As indicated, it can result in a negative calcium balance and osteoporosis, because calcium and other minerals are lost in the urine, along with the excess protein.
Calcium lost due to high protein diets must be handled by the kidneys, which contributes to the formation of painful kidney stones. Excess protein causes destruction of kidney tissue and progressive deterioration of kidney function. Many people in affluent societies have lost 75 percent of their kidney function by the eighth decade of their lives. Extra kidney capacity enables the kidney to carry out its function in otherwise healthy people, but for people who suffer from additional diseases related to the kidney, such as diabetes, surgical loss, or injury from toxic substances, damage due to the excess protein may be fatal. When people with partial loss or damage to their kidneys are placed on low-protein diets, they are able to maintain much of their remaining kidney function.
People on meat-based diets not only get excessive protein, but also large amounts of hormones, fat, cholesterol, pesticides, antibiotics, and other harmful ingredients that place major burdens on the consumer’s kidneys, liver, and digestive system.
Do vegetarians have to “complement” proteins, that is, get a combination of different foods containing proteins, to make sure that they get complete protein? This was a theory first advocated by Frances Moore Lappe, who mistakenly argued in the first edition of her very influential book, Diet for a Small Planet , that vegetarians should combine proteins in order to get the same “protein value” as meat. However, nutritionists no longer agree with that theory. The American Dietary Association stated in its 1992 paper, “Eating Well – The Vegetarian Way”, “Vegetarians do not need to combine specific foods within a meal as the old ‘complementary protein’ theory advised. The paper states: “The body makes its own complete proteins if a variety of plant foods – fruits, vegetables, grains, legumes, nuts, and seeds – and enough calories are eaten during the day.” Even Frances Moore Lappe agreed with this assessment in later editions of her book.
In summary, more and more scientific studies are finding that the best health results are obtained by shifting to completely plant diets, rather than shifting from red meat to poultry, dairy, and other animal products.