Whey Protein Side Effects

Beth Asaff

There is an ongoing debate about whey protein side effects and whether or not the dietary supplement is as harmless as many claim. Currently, there are only a few studies that show consumption of whey protein might be harmful to healthy adults. Despite this, there may still be times when adding whey protein to your diet is not recommended.

Whey Protein Side Effects

While whey protein is a natural food substance, it is not 100% risk-free. There are some minor whey protein side effects you should be aware of.

Allergic Reaction

Whey protein is derived from milk. In addition, some unrefined forms of whey protein contain higher levels of lactose. Consequently, the product may cause negative reactions in people who are allergic to dairy products and those who suffer from lactose intolerance. If you experience any of the following symptoms after consuming whey protein, contact your doctor immediately:

  • Rash or hives
  • Itching
  • Swelling of the lips, mouth, or throat
  • Wheezing or difficulty breathing
  • Excessive coughing
  • Diarrhea or blood in the stool (especially in infants)
  • Vomiting
  • Anaphylaxis

Kidney Problems

If whey protein is taken over the long-term, there is a risk of developing kidney disorders, including kidney stones. However, it is important to note that there isn't substantiated research that links excessive, long-term whey protein consumption with deteriorating kidney function. Regardless, many experts still insist that there is a risk and caution individuals to consume whey protein in moderation.

Liver Problems

In some cases, whey protein has been found to cause liver damage related to ketosis. Ketosis is characterized by elevated levels of ketones in the blood. Doctors consider the condition very dangerous, since it causes stress on the liver that might lead to liver damage.

Excessive Consumption

In studying whey protein side effects, doctors have found that some individuals who consume excessive amounts of the substance may experience the following symptoms:

  • Increased stool frequency
  • Fatigue
  • Loss of appetite
  • Headaches
  • Thirst
  • Bloating
  • Cramps

Better Safe Than Sorry

While the vast majority of consumers will not experience negative side effects while taking whey protein, it's better to be safe than sorry. Contact your doctor if you experience any signs of an allergic reaction or experience any of the aforementioned symptoms. Vegetarians looking to take additional precautions should consult their health care provider before incorporating whey protein into their diet.

Whey Protein Side Effects