Proteins excessive intake
Protein is an integral part of our diet, important for structural and other bodily functions. Protein has also been in focus lately, because of its role in weight loss. But the consumption of high protein diets over a long period of time has been associated with major health risks. Research does not support protein intake in excess of 2.0 grams per kilogram body weight.
Possible health risks associated with excess protein consumption
- Increased calcium excretion -- Many researchers think that excessive intake of protein leads to increased excretion of calcium. Calcium is leached from the bone to balance the increase in acidity arising from high protein intake. However, this effect is negated if the diet is rich in alkaline minerals (present in fruits and vegetables).
Some very high protein, very low carbohydrate diets induce” ketosis”. When there is not enough carbohydrate to be broken down into glucose for the cells, body breaks down fats for energy. As a result, ketone bodies are formed from fatty acids giving rise to a condition called ketosis. This basically increases the acid level in the body. To compensate for this metabolic acidosis, there is increased calcium resorption from the bone which could lead to increased risk of osteoporosis and possibly formation of kidney stones.
Following a high-protein diet for a few weeks probably won't have much effect on bone strength. But having it for a long time, though, could weaken bone.
- Effect on kidneys -- Extremely high amounts of proteins (more than 2.5 grams per kilogram body weight) over many years have been associated with decreased kidney function and possible kidney failure in some individuals. The nitrogen from the amino acids is removed and incorporated into urea which is then excreted by the kidneys. The increased urea production from a very high protein diet will overload the kidneys in the long term.
Other possible effects
- Liver dysfunction due to increased toxic residues -- Proteins have high amount of nitrogen. These are broken down to ammonia in the liver. Excessive proteins will lead to more nitrogen breakdown, thus leading to liver overload. Over a long period of time, this can affect the liver adversely.
- Vitamin B6 deficiency -- A high protein diet requires increased levels of vitamin B6. If this vitamin B6 need is not met, it can lead to its deficiency. There may not be need for lot of concern about high protein intake in healthy individuals (especially along with consumption of high carbohydrates). But genetics plays a major role in the development of health problems. Many high-protein diets could potentially be harmful to people who are genetically predisposed to a given health condition. Also, individuals with end-stage kidney disease must carefully monitor their intake of protein, as kidneys play a vital role in protein metabolism. Although more research is needed to define the optimal amount of daily protein, studies suggest that long-term high protein diets should be used with caution. Findings do raise concerns of increase in health problems with high protein, low carbohydrate diets over periods of extended use. Therefore, it is important to choose high protein foods judiciously. Leaner cuts of red meat, more of fish and poultry, vegetable sources of proteins like beans, nuts and whole grains will go a long way to keep the harmful effects of high proteins in check.
Therefore, the best thing to remain healthy is to have proteins in proper ratio with carbohydrates and fats, the diet comprising of lot of fruit and vegetable and leaner varieties of animal protein foods.
- Protein in nutrition/content/2/1/25
- Medscape & eMedicine