What are the side effects of consuming too much protein?
From the Field
If I am eating two grams of protein per body pound, will this have any side affects?
Proteins are found in every cell of our bodies; they are made up of amino acids, considered to be the building blocks of protein. Protein is not a primary energy source, as carbohydrates are, but it does contribute to energy production. In addition, it is essential for muscle contraction and the formation of muscle, hair, nails, skin, and other tissues, as well as repair of injuries. There is a notion that athletes should consume more protein to increase their muscle size. As for the balance equation of more going in than out, excess calories from protein are converted to and stored as fat, after your body removes the nitrogen. Also, large quantities of protein can strain the liver and kidneys because the nitrogen from the protein must be eliminated.
Recommended Dietary Allowance (RDA):
Men 19-50 – 0.8 g/kg/body weight/day total protein (approximately 56 g/day protein)
Women 19-50 – 0.8 g/kg/body weight/day total protein (approximately 46 g/day protein)
There is no evidence that consuming 0.8-3.6 g/kg/day of protein is associated with any adverse effects for healthy, active adult men and women. The Acceptable Macronutrient Distribution Range for adults 18 yr and older is 10%-35% of total calories. The recommendations for endurance athletes are 1.2 to 1.4 g/kg/day and for strength athletes, 1.2-1.7 g/kg/day.
At two grams of protein per pound of body weight, you would be consuming 4.4 g/kg body weight per day. Extra dietary protein must be broken down in the body, which increases formation and excretion of the nitrogen waste product urea. This additional waste increases fluid requirements and places a considerable load on the liver and kidneys. In some individuals, high protein intake can cause hypertension, increased fluid needs, diarrhea, abdominal cramps, and/or an imbalance of the essential amino acids.