As a Nutrition instructor, I am often asked this question, "Why is too much protein bad for us"? Let's first talk about why we need protein, the benefits it provides to the body as well as recommended daily needs. With a little background it will be easier to understand why too much can be dangerous.
Protein is necessary for growth and development. Protein provides the body with energy it needs to manufacture hormones, enzymes, antibodies, antibodies and tissues. Protein also helps keep the body in proper acid-alkali balance.
When you consume protein, it is broken down in the body into amino acids. Amino acids are the building blocks of all proteins. There are approximately 28 commonly known essential and non-essential amino acids. The body is able to make non-essential amino acids - therefore, it is not necessary to obtain these from the diet. Essential amino acids cannot be synthesized from the body and must be obtained from foods you eat.
Proteins can be in complete or incomplete form. Complete proteins contain all the essential amino acids. Sources of complete proteins include: meat, fish, eggs, poultry and milk. Incomplete proteins contain only some essential amino acids. These proteins include: grains, legumes and green leafy vegetables.
It is always best to get the protein you need out of the foods you consume on a daily basis. Most Americans get enough protein out of their diets. Protein provides approximately 4 calories per gram, which is the same as carbohydrates. If you are not sure if you are getting enough protein, a good rule of thumb is .8 to 1.0 grams per kilogram of body weight (this is for a non-athlete). Protein intake should be about 12 - 15% of total daily calories. Therefore, if you are consuming 2,000 calorie per day you would want 240 - 300 calories (60 - 75 grams) of protein. People with disease and advanced disease states as well as athletes will have different protein needs and requirements. These should be determined by a health care professional.
The body produces proteins as they are needed; should the body become depleted of its stores, it would not be able to produce the proteins that require those amino acids. Lack of protein in the body can have devastating and life long effects including digestive disorders, depression and stunted growth. Many factors can lead to a deficiency even with adequate protein intake. Impaired absorption, stress, trauma, infection, drug use, age and imbalances of other nutrients are a few of the factors.
Excessive protein intake is just as unhealthy as low protein intake. Too much protein stresses the kidneys and liver. Your kidneys and liver process the waste products of protein metabolism. Ammonia is a by-product of protein metabolism - ammonia is toxic to the body, so the body has to protect itself by having the liver convert the ammonia into urea. Urea is a much less toxic by-product of protein metabolism. Urea is carried through the bloodstream, filtered out by the kidneys, and excreted. As long as protein intakes remain normal and a person has no health defects, there is no compromise. When there is an excessive amount of protein intake and unnecessary stress is put on the body - toxic levels may accumulate.
It is essential to have a healthy balance when planning your daily meals. You need healthy combinations of lean protein (in adequate amounts), complex carbohydrates and heart healthy fats. Protein is essential to the body - however, like everything else that is good for us, "moderation" is key!
Angela Hattaway is a Nutritionist and Personal Trainer with over 15 years experience. She got her BS in Nutrition and Dietetics from Stephen F. Austin State University and she also has a Master's Degree in Business with an emphasis on Healthcare. Angela is experienced in working with both children and adults and loves working with clients to help them set realistic goals and expectations. She is passionate about nutrition and fitness and feels this comes through when she works with people. Angela loves giving clients the tools, motivation and encouragement they need to be successful throughout their lives. Visit her blog at blog.ultimatenutritionnfitness.com. She can be reached via email at at firstname.lastname@example.org.