How Much Protein Is Bad for the Liver?

Not all macronutrients are created equal. This family, including carbohydrates, fats and proteins, are the chemicals needed to sustain life. Proteins stand out amongst this group in that they contain nitrogen in addition to hydrogen and carbon atoms. Although nitrogen is essential for your body to create amino acids, the building blocks of life, it is also more taxing on your liver than other elements.

Protein is absolutely crucial for your body's growth and vitality. It regulates hormones, builds muscle and maintains your body's cell structure. Protein is also the key component in your hair, nails, bones, cartilage, skin, hair and blood. Furthermore, it manufactures important enzymes, regulates your body fluids and prevents infection. Thus, including the right amount of protein in your diet on a regular basis is an important part of staying strong and healthy.

Although little research is available, some studies indicate that too much protein can lead to long-term liver damage. Because the process of metabolizing protein leaves behind toxins that the liver must sort through, too much of it can be taxing and therefore impair the liver. According to W.C. Murray, author of "Essentials of Human Metabolism," the liver is responsible for maintaining an equilibrium of nitrogen in the body. As a result, when protein is ingested, the liver has to work even harder to manage this important homeostasis and to convert the synthesized protein into usable amino acids. If this balance is off, the body may become overly acidic. Some symptoms of an acidic body include decreased body temperature, headaches, paleness, inflamed eyelids and cornea, mouth ulcers and acid regurgitation.

However, there are a number of other complex factors that contribute to how effectively the liver breaks down protein, as well. Thus, most medical professionals agree that the risk of liver damage is much greater when one dramatically increases their protein intake over a short period of time.

So, what is the ideal amount of protein to incorporate into your diet? Experts disagree on exactly how much of your calories should come from protein; however, the average prescribed amount is 15 to 25 percent from a lean source. The Food and Nutrition Board who sets the national recommended daily allowance (RDA) suggests that you consume 0.36 grams per pound of your body weight each day. For athletes, the suggested dose is slightly higher. The American College of Sports Medicine, The American Dietetic Association and the Dietitians of Canada all recommend that highly active people ingest 0.55-0.64 grams per pound of body weight every day.

It is also possible to eat too little protein, though this doesn't effect the liver specifically. Eating less than 0.18 grams per pound of your body weight can lead to a protein deficiency, which is a very serious condition. Some of the most common early symptoms include a build up of fluid under the skin, weight loss, hair loss, sensitive skin, lethargy, headaches, insomnia, muscle cramps and deep ridges in your nails. You may also feel anxious, depressed and moody. If you experience any combination of these symptoms, be sure to see your doctor right away.

Overall, proteins are a part of a complicated process required to create amino acids in your body. When you maintain a balanced diet that includes complex carbohydrates, essential fats and protein, your system can harmoniously manage this process. Exercise also helps by triggering your body to break the protein you consume down into usable parts. As Dr. Gail Butterfield, Ph.D., R.D., the director of Nutrition Studies at the Palo Alto Veterans' Administration and a nutrition lecturer at Stanford University, explains, "Adding more protein but not more exercise or calories won't help you build more muscle mass, but it may put your other bodily systems under stress."