In the last post reviewed a small sampling of the mass of research showing that getting a balanced amount of protein (about third of our calories) from natural sources is healthy and helpful for long-term fat loss. So how did the myth that protein is bad for us get started in the first place?
The Protein is Bad for You Myth Debunked
The myth came out of studies where animals that were fed extreme amounts of protein experienced problems. However, rather than proving more protein is harmful, these studies prove that until we exceed two grams of protein per pound of body weight per day, we will get only healthier and slimmer by upping our protein intake.
“The Nurses’ Health Study is the only large prospective study to have examined the link between dietary protein and cardiovascular disease….The group of women who ate the most protein…were 25% less likely to have had a heart attack or to have died of heart disease…eating a lot of protein doesn’t harm the heart.” – W.C. Willett, Harvard University
To put two grams of protein per pound of body weight into perspective, an inactive 150-pound person would not enter the protein danger zone until they ate eleven chicken breasts per day, every day. That would total two grams of protein per pound of body weight, and would mean that 60% of their total calories were coming from protein. That is a terribly imbalanced diet and an unnatural amount of protein.
Bad things happen if we eat too much of anything. Luckily, it is nearly impossible to eat too much high-Satiety protein. Additionally, a natural increase in our protein intake will improve our cholesterol, triglycerides, and insulin regulation, while lowering our risk of cardiovascular disease. And it does not matter if the protein comes from lean meat. In fact, low levels of animal protein have been associated with an increased risk of strokes.
But The China Study Says Meat Is Deadly
Let’s focus on meat for a moment. There is nothing wrong with eating high-quality meat. Besides the fact that meat was a cornerstone of our diet for most of our evolutionary history, there is no clinical data showing that meat is unhealthy. The Journal of the American Medical Association reviewed 147 studies on the impact of diet on health. They found zero correlation between meat consumption and cardiovascular disease. Separately, researchers found that people in England have eaten about the same amount of animal fat—the source of most of the concern with meat—since 1910. Meanwhile, the number of heart attacks increased 1,000% between 1930 and 1970. It looks like animal fat is not causing the climb.
Similarly, during basically the same period of time in the U.S., a similar increase in heart attacks occurred while the amount of animal fats being consumed dropped. Meat is not unhealthy. It is a fantastic source of protein and therefore a key part of a natural balanced diet.
But Doesn’t Protein Weaken Our Bones?
Last but not least, at some point one of your more annoying coworkers will bring up some misguided magazine article arguing that protein promotes osteoporosis. This myth comes from the fact that digesting protein requires more calcium than the digestion of fat or carbohydrates. Certain individuals claim this finding shows that eating a lot of protein will suck calcium from our bones. That is inaccurate.
“Controlled human studies show that commonly used complex dietary proteins, which have a high phosphorus content, do not cause calcium loss in adult humans.” –H. Spencer, Edward Hines Jr. Veterans Affairs Hospital
First, you will not be eating a lot of protein. You will be eating the amount humans evolved to eat. Second, you will have no need to grab calcium from your bones since a natural balanced diet provides at least 150% more calcium than the typical U.S. diet (for example, leafy green vegetables are excellent sources of calcium. Calorie for calorie, spinach provides nearly twice the calcium as reduced-fat milk.). Third, protein digestion does not negatively impact bones if intake of the mineral phosphorus is increased, and a natural balanced diet does that. Finally, while more protein increases the need for calcium, it also increases the body’s ability to absorb calcium. When more protein is taken in, the body automatically makes better use of calcium. Studies show that a natural level of protein increases bone density by raising levels of the protein IGF-1.
With respect to adverse effects, no protein-induced effects are observed on net bone balance or on calcium balance in young adults and elderly persons. Dietary protein even increases bone mineral mass and reduces incidence of osteoporotic fracture. – M.S. Westerterp-Plantenga, Maastricht University
The only drawback with protein is the misinformation about concentrated sources of protein. Let’s cover that in the next post.
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