15 Unexpected Side Effects Of Whey Protein

Written by Tanya Choudhary
ISSA Certified Specialist in Fitness & Nutrition

Do you have whey protein? If yes, how much of it do you have on a daily basis? Whey protein is undoubtedly healthy and has benefits, but it does come with its own set of side effects.

Would you like to know more? Go ahead and read!

Whey Protein – A Brief

Although whey protein is considered to be a supplement that is safe, it is best not to go overboard with it. When you consume it more than you should, it can lead to a number of health problems. This risk is even higher when your intake of carbohydrate is low. Milk contains two types of protein; one of them is whey protein. It is water soluble and is used to meet the daily protein requirements. It also provides large amounts of L-cysteine, the amino acid. This amino acid helps in the alleviation of deficiencies that come with conditions such as diabetes aging (1).

Experts call whey protein the “complete protein” as it is rich in all the amino acids required by the human body to repair muscles, bones, tissues, organs, etc. Other complete proteins are foods such as eggs, meat, dairy, etc. One of the pros of whey protein is that it is easy to digest quickly.

[ Read: Side Effects Of Protein Supplements ]

Benefits Of Whey Protein

Although whey protein is consumed as a supplement, it is much more than that. It is a functional “super food” that helps immensely in the regulation of your body weight. It also helps in increasing muscle mass, and comes with many other health benefits. The health benefits that this nutrient provides are linked directly to the amino acid profile it has. This complete protein is also highly rich in antioxidants, making it an effective fighter against various diseases and a great promoter of overall health.

Here is a look at some of the benefits that you can gain by moderately consuming whey protein supplement of high quality on a regular basis:

  1. It helps in promoting weight loss.
  2. It helps in increasing muscle mass in the body.
  3. It helps in the treatment of cancer.
  4. It helps in reducing the symptoms that come with HIV.
  5. It helps in increasing the levels of glutathione in your body.
  6. It helps in lowering triglyceride levels in the body.
  7. It helps in lowering cholesterol levels while increasing good cholesterol or HDL.
  8. It helps in boosting the proper function of the immune system.
  9. It helps in increasing power while playing sports.
  10. It helps in lowering recovery time and the symptoms that come with over-training.

As you can see, there are quite a few benefits to gain from whey protein intake. The trick is to make sure that you do not take too much of it. Instead of gaining its goodness, you can end up with side effects that may not seem too severe but can be highly uncomfortable. If you have kidney, liver or heart problems, it is especially important to moderate your intake of whey protein and also get your doctor’s advice before you start making it a part of your daily diet.

When Should One Take Whey Protein?

This is a question that is often asked by many people who are interested in consuming whey protein but do not know how to go about it properly. It is not tough to learn when to take this protein to reap its benefits.

Firstly, if you want to take whey protein on its own, you should do it within half an hour to an hour after a workout that is based on strength training. This is because this protein gets digested very quickly. During other times, you should eat it with other foods so that digestion can be slowed down. For instance, for extra protein in your breakfast without foods like eggs, you can add whey protein to your oats in powder form.

Secondly, if you want to have a healthy snack while you are in the office, you can have a whey protein-shake combined with a bit of fish oil or nuts. This again will help in slowing down the digestion process of the protein. The fat combination is what helps slow down digestion and this in turn benefits you greatly by allowing the levels of insulin in your body to stay even. It also aids in the stimulation of CCK, which is a hormone that lets your body know when it is full.

Protein that is digested after a workout gives your body the amino acids that it needs for the repairing and building of new muscles. According to experts, consuming whey protein as soon as you complete a workout could be especially beneficial as it has a rich content of Leucine, an amino acid that is easily absorbed by the body.

Whey Protein Side Effects

Although whey protein has many benefits, it does come with quite a few side effects as well. Here is a look at fifteen of the adverse effects that this protein can have on your body:

1. Excessive Fat Gain:

In many cases, whey protein supplements have extra carbohydrates in the form of sugars. There are some that have fats as well. This means that weight can be gained in fat form, which is unhealthy. You can also gain weight when you overeat while consuming whey protein at the same time.

2. Kidney Stone Formation:

When you consume whey protein, there is a risk of kidney stone formation. While it may not be a direct cause, experts believe that this protein can make the condition worse if you are already suffering from it. To prevent this, you should take adequate quantities pf dietary fiber and water.

3. Digestive Problems:

Lactose is present in whey protein, and if you are sensitive to it, you could end up having problems with digestion. It is not only people who are lactose intolerant that suffer from this problem. If you do have digestive problems, opt for a whey protein concentrate as it does not contain as much lactose.

[ Read: Side Effects Of Soy Proteins ]

4. Risk Of Gout:

Although there is no evidence that whey protein is a direct cause of gout, it can worsen the problem if you already have it. It is also best to consult a physician before you start taking whey protein if there is a history of gout in your family.

5. Kidney Problems:

Excessive intake of whey protein can cause renal problems, especially if you already suffer from them. Experts recommend monitoring your whey protein intake and also consulting your physician before you start taking it. This way you can avoid any long-term damage to your kidneys.

6. Liver Problems:

Consuming whey protein excessively can worsen liver problems (2). This is why it is important to make sure that you consume the protein moderately at all times. It is also advisable to consult your doctor before taking whey protein, as it may interfere with the effects of the medication you are taking for your liver condition.

7. Risk Of Heart Disease:

Experts believe that consuming too much whey protein can have dangerous effects on people who suffer from heart disease. It can cause cardiac arrest, heart rhythms that are abnormal, and as well as complete loss of heart functionalities.

8. Blood Acidity Increase:

Another side effect of whey protein consumption is an escalation of pH in blood. When there is too much protein in your blood, the kidney has problems in metabolizing it. This results in the increase of blood acidity.

9. Development Of Osteoporosis:

This disorder has been linked to excessive intake of whey protein. This is especially risky with long-term intake of the protein. Consuming whey protein in high amounts can cause mineral imbalance in the bones which in turn can lead to the depletion of the density of bone minerals.

10. Fatigue And Weakness:

Due to the digestion problems that some people suffer from when they consume whey protein, they can also go through adverse effects such as extreme fatigue as well as weakness. They may also suffer from bloating, gas, cramps, etc. This is because some people’s bodies can’t process or break down the protein that they consume.

11. Development Of Ketosis:

This is another common side effect of whey protein consumption. This is a condition that occurs when abnormal levels of ketone bodies are present in the blood (3). If you put yourself on a diet that is low in carbohydrate and high in protein, energy is burnt in the body using fat. When there is no fat, protein is used. This puts immense pressure on the liver and causes damage over time.

12. Diarrhea:

Another side effect of excessive whey protein consumption is diarrhea. It is a part of the effect that this protein has on the digestive system. There can even be blood in the stool, especially among infants.

13. Wheezing:

Many people often have an allergic reaction to whey protein, especially if they are lactose intolerant. Such people can have difficulty breathing and may suffer from symptoms like wheezing. If you go through this symptom, you should consult a physician immediately.

14. Swelling Of Throat, Mouth, Lips:

Another symptom that comes with an allergic reaction to whey protein is the swelling of the throat, mouth, and lips. Although it may not be painful, it can be extremely uncomfortable, and it is best to see a doctor to make sure that no severe damage has been done.

15. Nausea:

This is one of the common side effects of taking whey protein. In quite a few cases, people also suffer from vomiting. The key to avoiding this uncomfortable side effect is to cut down on your intake of the protein.

How Safe Are Whey Protein Supplements?

Are you aware of the serious side effects of whey protein supplements? It has been established that the amount of whey protein supplements you consume has a direct influence on whether you gain from its benefits or not. Over-consumption of this protein is the reason many people suffer from adverse effects. In fact, excessive consumption of any protein is bad for the body as it gets stored in the body in the form of fat. This in turn increases the risk of dehydration.

There is also the chance that whey protein may have an interaction with certain medications. For example, it has been found that supplements made with this protein can reduce the effectiveness of Levodopa, which is a drug used for Parkinson’s disease. Whey protein supplements may also lower the effectiveness of Alendronate, the drug prescribed to patients with osteoporosis. It may lower the body’s ability to absorb the drug, thereby making it less effective. It may also have an adverse effect on the effectiveness of the antibiotics Tetracycline and Quinolone. It should also be noted that diabetic patients may experience blood sugar changes when they consume protein supplements.

To make sure that whey protein supplements are safely consumed, experts recommend moderate doses on a short-term regimen. This way, the body gets the benefits of the protein without the risk of suffering from any of these whey protein side effects that have been mentioned above. They also recommend whey protein supplements for athletes or people who are physically active than for those who are not. This is because athletes or people who work out on a regular basis require more protein than people who are not physically active.


As with all health or dietary supplements, it is important that you consult your doctor before you start taking a whey protein supplement. This will ensure that it is safe for you and will not interfere with any medication that you may be taking. While whey protein may work wonders for someone you know, there is no guarantee that it will provide you with the same results. In fact, you may worsen any condition that you may be suffering from.

It is also important that you stick to the proper dosage when you start taking whey protein. Remember that it is not the protein itself that is harmful, but its over-consumption. Many people make the mistake of taking in more than the recommended dose as they believe that it will provide them with quicker results. It is important to know the whey protein benefits and side effects thoroughly before you consume it, the better it is for your health as you avoid all the side effects that come with it.

Do you know any other side effects of whey protein? Please share with us in the comments section below!

Recommended Articles:

Was this article helpful?
The following two tabs change content below.
The one with a constant energy that can leave you awed, Tanya can jump around and talk for the whole day. If not found writing away the desired articles, she can easily be spotted glued to the youtube, eyes wide, spazzing over the perfection of her favorite singer. Functioning without music (Bollywood, Hollywood, Spanish, German, Korean, Chinese, Japanese, Thai and what not- Because music is music), and a big cup of tea is an impossibility for her. Ever heard of a totally weird soul that could go frenzy over the smell of a book, especially if it's a Dan Brown or Lee Child? Yep! That would be her.