Protein Sports Nutritionist Eoin Lacey and Jeff Willoughby
What is protein and how is it beneficial to you?
There have been a couple of myths out there in the general public about nutrition plans that consist of higher than usual proteins levels that is recommended by the FSA. Lets have a look at these one by one and unravel the truth behind each one.
1. High protein diets cause kidney disease
This myth comes from 2 different sources as far a I can find. The first is by reversing a medical fact. That fact is that people with a preexisting renal function, a low protein diet seems to lessen the decline of the kidney. Therefore people have concluded that high levels of protein lead to impaired kidney function.
Jonny Bowden sums it up in a very simplistic way in his book "Living Low Carb: Controlled Carbohydrate Eating for Long Term Weight Loss".
"If you have a broken leg, or a sprained ankle, or shin splints, Iʼm going to suggest that you not take a step class until the injury heals. Under these special circumstances, the very weight-bearing that does so much good for the normal person is going to be more stress than you need during the healing phase. Iʼm going to tell you to stay off the leg, let it heal, and avoid putting additional stress on it at this time. Does the fact that step class is not good for a person with a broken leg mean that the step class led to the broken leg? No. And ketogenic diets do not—I repeat, do not—cause kidney disease. If your doctor says they do, politely ask him or her to show you the studies. (They donʼt exist.) Ketogenic diets are, however, not a good thing if you have an existing kidney disease, much the way a step class is not a good thing if your leg is already broken".
So yes, one study with only 8 people with renal failure showed that a high kidney diet did not help the kidney to repair. This is completely different from having healthy subjects eat a high protein diet and concluding that this is bad.
Louis Newburgh was a scientist who worked in the era of the 1920s, also claimed that inducing a diet high on protein would elicit chronic kidney problems. However his research was not done in the most compelling way. His research was done on Rabbits. These are animals that do not eat meat (their diets are largely based on buds and bark). So he fed herbivores diets high in egg whites, beef protein and noticed that this diets caused kidney problems with rabbits. Once again flimsy research was interpreted at a stretch that therefore the same thing that happened to herbivores (the rabbits) would also happen to meat eating humans. This is simply not the case.
What really causes the liver to be stressed? It is sugar-sticky proteins that are a result of excess sugar floating around in the blood stream bumping into protein molecules. These sugar-sticky molecules start to clump together becoming to big to pass through the network of blood capillaries in the kidneys that act as a filter system for waste products form the blood. This reduces kidney function. If you donʼt currently have a kidney problem, then eating a low carbohydrate (and hence high protein diet) is an ideal way to control blood sugar levels which eventually could lead to kidney disease.
2. The absence of fresh fruit and vegetables in these diets would cause mineral deficiency diseases.
B vitamins are depleted from the body by the consumption of carbohydrates and the same can be said for vitamin C. Type 2 diabetics have roughly 30 percent lower levels of vitamin C in their circulation than do non-diabetics. Metabolic syndrome is also associated with significantly lower levels of circulating vitamin C. The explanation that Gary Taubes gives in his book Good Calories Bad Calories is from 1997 by the nutritionalists Julie Will and Tim Byers of the center of disease control and the university of colorado respectively. They suggest that the high blood sugar and/or high levels of insulin work to increase the bodyʼs requirement for vitamin C. The vitamin C molecule is similar in configuration to glucose and other sugars in the body. It is shuttled from the bloodstream into the cells by the same insulin-dependent transport system used by the glucose. So hence they compete in this process. Because blood sugar is favoured in this competition, vitamin C is globally inhibited when blood sugar levels are elevated. Hence if if blood sugar goes up, vitamin C uptake drops accordingly.
So therefore it is not the absence of fresh fruit and vegetables that maybe causing deficiencies, it is the presence of blood glucose from refined carbohydrates that do the damage. Infact you could be eating fresh fruit and vegetables and still be minerval and vitamin deficient due to the high presence of blood glucose.
"When we discuss the long-term effects of diets that might reverse or prevent obesity, we must not let our preconceptions about the nature of a healthy diet bias the science and the interpretation of the evidence itself"
Gary Taubes. Good Calories, Bad Calories.