More Protein Dangers continued...
What happens to bone when people eat very high-protein diets for a long time? This hasn't been studied, but it's likely to be associated with increased bone loss. But the answer isn't a very low-protein diet since the recommended amount of protein is needed to keep bones strong as well.
* Higher meat protein could mean higher colon cancer risk
Reviews of the literature on colon cancer suggest that though a high-protein diet, per se, doesn't l increase your colon cancer risk, a diet high in meat may be the ticket that does increase the risk. Following along these lines, a recent Japanese study concluded that as dietary animal protein and fats and oils increase, incidence of colorectal cancer increases as well, but colorectal cancer incidence decreases as dietary plant protein increases (along with amounts of carbohydrates and cereals).
* Don't regular exercisers need more?
The answer is "probably not." The Institute of Medicine's Dietary Reference Intakes report recently released concluded: "In view of the lack of compelling evidence to the contrary, no additional dietary protein is suggested for healthy adults undertaking resistance or enduring exercise."
But What About All That Weight Loss?
Is it the protein or the calorie cuts that lead to weight loss? The high-protein diet programs and gurus will most certainly tell you it's the protein. But two recent studies say it's the restriction of calories rather than the protein that is the most important determinant of weight loss. In an Australian study, 36 obese adults, mostly women, were assigned to a 12-week energy-restricted diet that was either moderately high in protein (27% calories from protein) or lower in protein (16% calories from protein). The weight loss was similar in both diets. Researchers at Stanford University analyzed all research published on low-carb or ketogenic diets over the past 37 years. They concluded that the successful weight loss from low-carb diets was "principally associated with decreased caloric intake and increased diet duration but NOT with reduced carbohydrate content."
One of the most popular features of the low-carb, high-protein diet is the quick weight loss. Don't be fooled here. You cannot physiologically lose more than 2 pounds of body fat a week. So what are all the pounds that people lose in the first few days of starting the diet? Water. To make up for the lack of dietary carbohydrates, the body uses its own carbohydrate stores in the liver and muscle tissue (called glycogen), which in the process also mobilizes water. Many of the early and rapid pounds lost are due to -- that's right -- excessive urination!