Fact Checked

7 Undeniable Long-term effects of Whey Protein

Yes, There are number of long-term effects of whey protein on the human body. Effects can be both positive and negative, and they vary from individual to individual. Some people may experience beneficial effects, while others may experience side effects. We’ll discuss later why some people see side effects and why some people see beneficial effects. But first, let’s talk about the major and most common benefits and side effects of consuming whey protein over a long period of time or on a regular basis.

long-term effects of whey protein

  1. Muscle Growth
  2. Effective for bone health
  3. Helps with weight loss
  4. Digestion problems
  5. Acne problems
  6. May cause liver damage
  7. May cause kidney damage

What is whey protein?

In, 2023 I’m sure practically everyone reading this blog knows what whey protein is, but just in case, let me explain it in layman’s terms. Whey protein is a protein blend made from whey; if you want to learn more about what whey protein is, continue reading.

Whey protein is by far the most well-known and widely used supplement in the supplement industry; almost everyone who goes to the gym or participates in any kind of fitness activity consumes whey protein to meet their daily protein requirements. The more physically active we are, the more protein our bodies require because it is responsible for the recovery of our body’s muscle tissues.

Completing your daily protein intake keeps your body healthy. However, studies suggest that we don’t necessarily require whey protein to complete our daily protein intake; we can do it by maintaining a balanced diet or increasing calories via protein in our diet. Some experts claim that whey protein has some adverse effects. Let’s take a look at the long-term effects of whey protein. I split it into two categories: beneficial and adverse whey protein effects.

Long-term benefits of Whey Protein

It promotes muscle growth

If you didn’t already know, the structural components of our cells and tissues are proteins, and proteins are also responsible for the growth and maintenance of those cells and tissues. Protein makes up about 80% of the total mass of a muscle.

So, whey protein is an excellent source for muscle maintenance and growth because it is a complete protein, containing all 20 amino acids, 11 of which are considered essential amino acids and the other 9 of which the body can produce on its own. A protein molecule is composed of 20 amino acids. 

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Image by jcomp on Freepik

It is Effective for bone health

As we know, whey protein is a by-product of dairy items like cheese. Because all dairy products are derived from milk, whey has milk-like properties. Milk is loaded with a variety of minerals that are beneficial to bone health, especially calcium and phosphorus.

On osteoblasts (the formation of bone), it enforces powerful anabolic effects, and it also prevents the development of osteoclasts (bone breakdown).

It Helps with weight loss

Many fitness and nutrition experts have suggested that a high-protein diet is beneficial for weight loss. I agree with them, but have you ever considered why? “Why a high-protein diet is good for weight loss” Okay, let’s get started. I’ve done some research, and I’ll keep it brief because we’ll cover the entire topic in another article.

We mostly use the calorie restriction method during our weight loss journey, but as a result of losing weight, we also lose muscle mass. Whey protein will help with statiety by keeping you full and providing you with protein-rich calories.

While whey protein helps with satiety and provides a good source of protein-rich calories, it is important to note that it is not a complete replacement for all other calorie sources.

It improves body composition and decreases waist circumference because the majority of fat loss occurs in the legs, stomach, lower back, and gynoid region, and who knows, you may start developing your abdominal muscles.

When combined with physical activity, it is the most effective protein for promoting fat loss while remaining faithful to a calorie-restricted diet.

Also, read our article on “5 Best Ways to Remove Smell from Protein Shaker Bottle

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Long-term side effects of whey protein

Therefore, there are many misconceptions, myths, and rumors that circulate about the adverse effects of consuming whey protein. Some people believe it will harm the kidneys, cause hair loss and have other side effects. Some believe it is harmful for women or that whey is not natural. However, the vast majority of these false beliefs are just rumors. Although, There are some negative effects associated with using whey protein.

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Image by 8photo on Freepik

It may cause digestion problems

Bloating, abdominal cramping, constipation, gas, and diarrhea are all possible side effects of consuming whey protein. In a nutshell, some individuals are unable to digest whey protein, and the vast majority of the time, this problem arises in individuals who are lactose intolerant (“lactose intolerance is when your body is unable to break down or digest lactose”).

Whey protein is a by-product of milk products, and since lactose is a sugar that can be found in milk and milk products, it follows that lactose can also be found in whey protein.

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It may cause acne or make it worse

Whey protein can, in fact, contribute to acne or make existing acne worse. Whey is the primary factor in the elevation of IGF-1 (“IGF-1 is an anabolic hormone, meaning it helps with growth, including muscle gains.”). Whey protein causes an increase in insulin-like growth factor 1 (IGF-1), which in turn helps boost testosterone levels, but it is not good for your skin because it will cause acne or even make your acne worse.

Puberty is associated with an increase in IGF-1 levels, which helps explain why so many adolescents struggle with acne. Whey protein should be used with caution during adolescence, and it should even be avoided for a period of time. Adults, if it causes or worsens existing acne, avoid it for a while or consult a doctor about whether you should continue using whey protein.

It may cause liver or kidney damage

There are numerous rumors that long-term whey protein consumption can cause liver or kidney damage. Let us find out to what extent these rumors are true.

Does whey protein damage liver?

It has been shown that eating a lot of protein is good for the liver, and the nine essential amino acids in whey protein are good for the liver’s health and for repairing damaged tissue.  

According to a clinical nutrition study, 11 obese women were given 60 g of whey protein for four weeks, and it was discovered that whey protein is beneficial for fatty liver disease because it helps reduce fat inside liver cells.  

The American Journal of Gastroenterology published a rare case in which a 42-year-old male developed liver damage as a result of taking whey protein and creatin supplements.

A user on Quora claims to have NAFLD (non-alcoholic fatty liver disease) and says that the main cause is whey protein. Many other users claim the same in the comment section.  

However, there is insufficient evidence or case studies to prove that whey protein harms your liver. We recommend that you consult your doctor before taking whey protein supplements, especially if you have cirrhosis or NAFLD (non-alcoholic fatty liver disease).

Does whey protein damage kidneys?

Your kidneys’ primary functions are to remove waste from your body by converting it to urine. Essentially, they filter all of the fluid in your body.

It has been discovered that individuals who already have kidney disease may harm their kidneys by consuming whey protein supplements. This is because consuming whey protein supplements places additional strain on your kidneys.

However, it is safe to consume whey protein on a daily basis for a healthy person who does not have any kidney disease; your kidneys will simply work a little harder to process the extra protein.

We thoroughly discussed the main and most common long-term effects of whey protein. It brings up the question of why some people experience side effects and others experience positive ones.


Why do some people experience side effects while others experience benefits?

The answer is simple: approximately 65% of the world’s population is lactose intolerant, which means they have lost the ability to digest lactose. People who are lactose intolerant will almost certainly be unable to digest whey protein, causing digestive problems. We recommend whey isolate, soy, or egg protein supplements.

On the other hand, our growth hormone is most active during the teenage years, and it is the main cause of acne during this time, and whey protein also triggers IGF-1 (growth hormone), which causes acne or worsens your current acne condition. So, if you have acne and are a teenager, we suggest you should avoid whey protein or stop using it and for a adult, talk to a doctor if acne appears after you consume whey protein.

There is insufficient evidence to prove that whey protein causes liver or kidney damage, but if you have any liver or kidney disease, consult your doctor before consuming whey protein.

Whey protein is excellent for healthy people who do not have any of the issues listed above. It is a great source of protein; it has a complete amino acid profile; it contains all of the essential amino acids; it is great for completing your daily protein intake; it is great for muscle growth; it is great for weight loss if used correctly; it is great for bone health; and it has many other benefits.


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Hi, My name is Moksh Sethi, and I'm a certified personal fitness trainer and sports nutritionist who has worked with different clients for more than 3 years. I write about everything to do with fitness and nutrition, and I try to add the most vital insights I've learned over the years.

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