Whey Protein Isolate Side Effects

Whey Protein Isolate Side Effects

Whey protein is touted as the best in proteins for supplements – that may be true for a lot of people but not necessarily for everyone.

Whey protein is one of the two types of protein that comes from milk which also contains casein.  Casein is the protein which forms into “curds”.  It is used in some protein supplements and is part of the protein that is claimed as “milk proteins”.  Casein is a high quality protein but is more difficult to digest – it is used in fitness supplements and protein shakes for its “staying power” as it takes longer to absorb.

Whey is the major protein type found in the clearish liquid that remains after the curds are removed – as in “curds and whey” from the “Little Miss Muffet” children’s rhyme.  Little Miss Muffet was actually eating clotted milk curds and the liquid.

Whey is easier to digest than casein and contains a high amount of essential amino acids.  Commercially it is used in foods such as baby formula, soups, ice cream, breads, and other products which need to claim “high protein”.  Whey is used to help treat and prevent illnesses including heart disease, bone loss and diabetes and is routinely prescribed for illnesses that cause “wasting” such as AIDS and cancer.

It is also considered the “best” in protein supplements by a lot of fitness experts because of its “completeness” in terms of amino acid content and its ability to be digested easily.  Though most people can tolerate and easily digest whey protein isolate, it may have a number of side effects for some people.

Whey Protein Benefits

Whey has been shown to improve allergy symptoms in some people, though it can cause allergic reactions in others.  There is good evidence to support its use in reducing appetite and improving blood sugar levels.  This may help people with diseases such as diabetes as it can also help to promote weight loss if a person is not hungry and their blood sugar levels are maintained at a more consistent level.

Protein supplements in general have been used for many years in the fitness industry to provide protein needed for muscle growth and endurance.  Most people who work out routinely, particularly those who are interested in bodybuilding or other weight training and strength activities find that a “regular” diet does not provide enough protein to accomplish their goals.  Attempting to increase your protein intake with food can cause you to consume too many calories – which means that you will need a protein supplement.

For many years, “milk” protein containing a combination of casein and whey was the only choice for protein supplements.  Soy protein was introduced when some became interested in avoiding animal products; however soy has issues as it may not be a complete protein and it may cause “estrogenization” as it contains estrogen-like phytochemicals which may encourage feminization and actually prevent muscle growth.  In addition, excessive consumption may increase the risk of feminization which can theoretically lead to similar problems to those caused by hormone supplementation.

Technology has allowed us to separate the protein contained in milk to its components of casein and whey.  This has allowed us to provide supplements that contain only one or both of the proteins.  Casein has its advantages in supplementation as does whey protein.

Pure whey protein is good for those who are lactose intolerant as the lactose sugars contained in milk have been removed.  It may also increase glutathione levels in those who are deficient such as HIV patients – and increases glutathione levels in those who simply need more which benefits both the heart and the skeletal muscles.

Whey Protein Isolate Side Effects

Whey protein can improve the nutrient level of the diet and may have positive effects on the immune system but may also cause side effects for those that use it, particularly in large amounts that are needed in muscle building.

Whey protein side effects may include:

  • Increeased bowel movements due to extra protein load
  • Bloating in the digestive system due to protein digestion
  • Cramps in the digestive system for the same reason
  • Thirst
  • Nausea
  • Reduced appetite
  • Some people also experience side effects that may or may not be related such as
  • Nausea
  • Headaches
  • Fatigue

Even though whey protein is usually completely isolated from milk sugars when used as a supplement, some experts advise avoiding whey protein if you are allergic to milk.  Lactose intolerance is different from an actual allergy and may cause bloating, diarrhea, cramps and excess gas.  A true allergy would result in difficulty breathing, congestion, and rash but many people do not know which part of the milk they are allergic to and it is difficult to ensure that the product you are choosing is completely separated from other milk components.

For the most part, whey protein isolate side effects are rare or not severe, except in the case of a true allergy to the whey protein itself or difficulties in organ systems such as:

  • Kidneys
  • Liver

Organ function may be impaired by whey protein due to an overload of protein itself – not specific to whey, but to protein in general.  Symptoms of organ involvement may include abdominal pain, discolored urine, swelling and yellowing of the skin. Any severe symptoms of a reaction to whey protein including allergic reactions and organ-related symptoms should be reported to a physician.  An allergic reaction should be considered a medical emergency.

Whey Protein Interactions

There are certain medications which may interact with whey protein.  This is often due to decreased absorption in the gastrointestinal tract but not always.  Whey protein may interact with medications such as:

Levodopa – most commonly used for movement disorders such as Parkinson’s disease or due to side effects from some psychiatric medications.  Whey protein may decrease the amount of levodopa which is absorbed by the body.  This will decrease the effectiveness of the medication and may lead to a return of disease state symptoms.  People who are taking levodopa are advised not to take whey protein supplements and should not consume dairy products at the same time that the medication is taken.

Alendronate – also known by the brand name Fosamax, is used to decrease bone loss in osteoporosis.  Whey protein has been shown to decrease bone loss overall as it increases muscle strength which maintains bone but people who have osteoporosis and are taking alendronate may experience decreased effectiveness of the medication.  People who are taking alendronate should not take whey protein within two hours of taking the medication.

Quinolone type antibiotics such as levofloxacin, ciprofloxacin and others – may also decrease the amount of medication that is absorbed when taken at the same time.  This will make the medication less effective in treating the infection it was prescribed for.  Whey protein should not be consumed at the same time or within an hour of taking a quinolone antibiotic.  Any antibiotic with the warning “Do not take with dairy” should not be taken at the same time as whey protein.

Tetracycline type antibiotics – similar to quinolone antibiotics, should not be taken at the same time as whey protein.  The protein may bind to the antibiotic and make it ineffective to lack of absorption.  Common tetracycline antibiotics include tetracycline, minocycline and doxycycline.

Anti-diabetic medication – may be increased in effectiveness by whey protein.  As whey protein may lower blood sugar levels, those taking medication for diabetes may find that their blood sugar is too low.  People with diabetes should closely monitor blood sugar levels and consult a physician who may recommend medication adjustments. 

Anti-hypertensive medication – may be increased in effectiveness by whey protein as it may lower blood pressure levels.  Caution is advised in those taking medications that lower blood pressure.

Blood thinners – whey protein may increase the risk of bleeding in those who take blood thinners such as aspirin, warfarin, heparin, clopidogrel and even some non-steroidal anti-inflammatory agents such as ibuprofen or naproxen.

Medications metabolized by the liver – may show altered medication levels which could result in changes in how well the medications work.  People who take any medications should check with a pharmacist or physician before using whey protein supplements.

Dosing of Whey Protein

Doses up to 50 grams in one serving are generally considered safe for everyone.  Higher doses may be used by athletes and fitness enthusiasts and are recommended in doses such as:

1.2g-1.5g/kg of bodyweight as the total daily amount in combination with muscle or strength training.

For a 180 pound man, this would be 100 to 125 grams of whey protein in divided doses.  For a 150 pound woman, this would be 80 to 100 grams in divided doses daily.  The calculation is performed as:

Body weight in pounds divided by 2.2 kilograms per pound x 1.2 = lower recommendation

Body weight in pounds divided by 2.2 kilograms per pound x 1.5 = upper recommendation

Whey protein is one of the best protein sources in protein supplements but you should make sure that you are choosing a supplement manufacture of a reputable brand and quality.