Pure Protein Diet

First, there is no such thing as a pure protein diet. If you eat any sort of food, you also consume fat, fat soluble vitamins and minerals.

While protein is essential to good health, it is not the only ingredient needed for healthy metabolism. Current high protein diets also prescribe low carbohydrate intake. If you can't tolerate carbohydrates because of hypo or hyperglycemia after eating a high carb meal, low carb diets can be good for you.

High Protein and Weight Loss

However, consuming pure protein is not only impossible, but such a radical diet can not supply all the ingredients your body needs for healthy metabolism.

According to Dr. Michael R. Eades, the author of Protien Power, "The liver requires energy to convert the protein to glucose. The energy comes from fat. As the liver breaks down the fat to release its energy to power gluconeogenesis, the conversion of protein to sugar, it produces ketones as a byproduct. And what a byproduct they are. Ketones are basically water soluble (meaning they dissolve in blood) fats that are a source of energy for many tissues including the muscles, brain and heart. In fact, ketones act as a stand in for sugar in the brain." As a result, dieters on high protein/ low carbohydrate diets experience rapid weight loss.

Real Protein Needs

According to The American Journal of Public Health, published in 1943, the amount of protein in the diet, (when other nutrients were also provided) did not affect the health or fitness of the study's participants. However, the study found, a diet high in protein (not pure protein) increases the absorption of calcium and essential B vitamins like niacin and riboflavin. They also cited studies of Eskimo's traditional diets high in protein and fat, finding Eskimos enjoyed superior bone and teeth health. However, Eskimos also ate the raw organs, providing them with the vitamins and minerals other people get from fruits and vegetables. This is not part of the current high protein trend.

Carnivores vs. Omnivores

When you think of carnivores, you probably think meat eater. But even large cats, one of the Earth's most carnivorous species, have metabolisms designed for high protein. Yet, they don't eat pure protein. Consuming the entire animal means large cats also ingest the contents of their herbivore prey's stomach--getting their veggies. For example, a rabbit provides about 1/3 lean protein, 1/3 bone and 1/3 vegetable--a balanced carnivorous diet.

Rats, at least, have shown the ability to adapt their metabolisms to digest a very high protein diet. According to the Journal of Nutrition, the change in diet triggers gene expression of specialty enzymes to break down the proteins. In a study between high protein diets (P50) and the control group (P14), the P50 rats showed increased enzyme activity. "Similarly, the activities of alanine aminotransferase, arginase and serine dehydratase were significantly higher in the liver of P50 rats compared with P14 rats."

While too little protein will result in the consumption of the body's own tissues, too much remains a topic of debate. According to the Journal of Nutrition's, "Metabolic Consequences of a High Protein Diet," excessive protein intake can result in metabolic acidosis. This condition has been linked to muscle wasting, poor thyroid function and insulin resistance. The journal reports, "An association between high-protein intake, renal acid and calcium excretion has been reported." This means a chronic acidic state can lead to calcium depletion and bone loss.

Happily, the cure for acidosis is fresh fruit and vegetables. Remember, while we were not designed to live on pure carbs, we can not subsist on pure protein, either. Human beings evolved as omnivores, not carnivores--so forget about a pure protein diet. Limit your carb intake, and eat plenty of organic fruits and vegetables.