What Are The Dangers Of Prolonged Use Of Whey Protein?

Whey protein is a nutritional supplement isolated from a by-product of cheese production. It is available in powder and liquid forms and is marketed mainly toward athletes to promote muscle growth and recovery, particularly when combined with resistance training. Several adverse effects are possible with long-term whey protein supplementation. Talk with your doctor before you start taking these supplements to see whether they are right for you.

Kidney Damage

Long-term use of excessive amounts of whey protein may cause kidney damage. Excess protein increases the amount of ketone bodies -- a natural by-product of protein metabolism -- in your blood. Ketone bodies are normally filtered out by your kidneys and excreted in your urine. If there are more ketone bodies than your kidneys can handle, your kidneys may suffer cellular damage as a result.

Bone Loss

Excessive long-term whey protein intake also may cause bone loss. According to a 2008 study published in the "Journal of Bone Mineral Research," investigators found that while some protein is needed to maintain proper bone health, excess protein may be a contributing factor to the development of osteoporosis, depending on what else is in your diet. For instance, the researchers noted that the risk of bone mineral loss increased in some instances when protein intake was excessive and dietary calcium intake was low.

Metal Accumulation

Some protein supplements may contain heavy metals such as arsenic, cadmium, mercury and lead, according to a CBS News article reporting on a Consumer Reports review of 15 protein supplements. Although the manufacturers said that the supplements tested contained traces of these metals that were within the Food and Drug Administration's guidelines, excess intake could increase the risk of metal accumulation in your body, which has toxic effects.

Incomplete Nutrients

According to Katherine Zeratsky, a nutritionist with the Mayo Clinic, if you rely too heavily on protein shakes, you may not be getting all the nutrients your body needs to function properly. Zeratsky recommends using protein shakes sparingly and in addition to whole foods so that you don't deprive yourself of essential nutrients. She states that as long as you are eating a healthy diet that includes 46 g to 56 g of protein daily, supplements may not be necessary.