Kidney stones are a major concern for those that have experienced them in the past. If you have never had to pass a kidney stone, count yourself lucky.
For avid gym goers and fitness enthusiasts, though, the question remains. Will a pre-workout supplement cause kidney stones?
This review will examine the leading causes of kidney stone development. We will look at the research to find out what, if anything, in pre-workout supplements can cause kidney stones and how you can avoid them.
What Are Kidney Stones? (4 Types Explained)
In short, they are solid masses formed in the kidneys. However, there are different types that you should be aware of.
1. Calcium Stones
Calcium is, by far, the most popular type of stone, accounting for over 80% of all kidney masses produced. There are two main types of calcium stones, though, phosphate and oxalate.
Calcium oxalate stones are much more common as these come from our diet and supplements taken on a regular basis. Calcium oxalate is found in things like chocolate, spinach, beets, wheat bran, and some berries.
2. Struvite Stones
Struvites are large, painful, and form quickly. Unlike other masses from deposits or acids not being properly filtered, these stones occur from urinary tract infections. When you have a UTI, it can alter the pH of your urine, which prevents some minerals from being dissolved.
As these minerals build up they create solids that can be larger than others and appear much faster in your kidneys.
3. Uric Acid Stones
Uric acid is a waste product produced when proteins and some amino acids break down. Normally, the acid is fully dissolved in our urine and passes out when we go to the bathroom.
However, if there is excess uric acid, it can start to crystallize before it dissolves, leading to the formation of these stones. Their number, size, and density are determined by the amount of uric acid in the body.
Sharp pain and a burning feeling when you urinate are the most common symptoms. At a recent annual meeting, the Endocrine Society found water intake levels may help.
Some believe that adequate hydration and high doses of vitamin C can have a higher impact on reducing the negative effects of uric masses and may reduce a person's risk. Your doctor will know more, of course.
As with any mass, blockage, or shooting pains, you should always seek the advice of your doctor before starting any treatment or curative routine.
4. Cysteine Stones
Cysteines are most common in children and are linked to genetics. These hereditary masses are formed with Cysteine, an amino acid that isn't metabolized. Unlike other kidney products, Cysteine is reabsorbed through the kidneys and not expelled in the waste.
However, when there is no re-absorption, it can cause cystinuria and eventually the formation of the stones1].
[It was previously thought that these types of masses were only found in infants, but research suggests that the hereditary masses can last long into childhood and even into the late teens.
Does Pre-Workout Cause Kidney Stones?
No, normal pre-workout supplements or their ingredients in healthy adults don't directly link to developing kidney stones.
Kidney stones, or renal calculus, are a medical condition where hard masses form inside the kidneys. Calcified masses can rip, tear or block kidney function and tissue, causing pain and discomfort until they pass through the urinary tract.
A few things can lead to their formation, and a genetic predisposition is the primary factor. For healthy adults, there is no research that correlates between kidney stones and pre-workout formulas.
What has been studied and shown to be highly accurate is that if you are already at risk for kidney stones, supplementation of vitamin D and animal protein may increase the risk of kidney stone development.[2]
J. Christopher Gallagher, MD, Professor of Medicine and director of the Bone Metabolism Unit at Creighton University Medical Center, Omaha, Neb., said of the study's findings, "Pending further information, people should not exceed the guidelines suggested by the Institute of Medicine, which are 800 international units of vitamin D, and 800-1,200 mg per day of calcium."

In Which Cases Can They Affect Kidney Stones?
While studies may say one thing, actual practice can say another. For example, certain ingredients and supplements added to some pre-workouts may cause or help initiate the formation in those that are predisposed.
Chronic kidney disease, too much salt in the diet, and other factors can also lead to these calcifications. You should always seek professional medical advice when starting a new supplement regimen.
Let's find out just what the main ingredients pose as threats to your health.
1. Protein Content
Protein creates uric acid as it breaks down. This acid needs to be removed from the body and does so through the kidneys.
However, BCAAs in pre-workouts also break down into uric acid, and this might lead to the crystallization of the acid that can, in turn, lead to the formation of kidney issues.
Monitoring your protein intake levels and staying within your daily recommended values, as well as staying properly hydrated, can negate this risk of kidney stones.
2. Mineral Content
Minerals can also lead to kidney stone formation. You will want to monitor the number, type, and amounts of minerals in your diet and pre-workout powders. More calcium can cause the development of stones, much like uric acid.
Calcium can build up in the kidneys, and if you don't remove it, it will form kidney stones. Their size and number are determined by the amount in the body over the recommended daily amounts.
Learn More - Protein Powder Vs Pre-Workout
3. High Caffeine Intake
Supplement formulas use stimulants like caffeine to give you that coveted energy boost. However, caffeine is also the leading cause of dehydration in active individuals, and high levels of caffeine can impede the removal of toxins from your bloodstream, digestive system, and kidneys.[3]
When you are dehydrated, the oxalate forms more readily and can lead to kidney stone development. Therefore, you will need to properly hydrate throughout the day to reduce the risk.
Learn More - How Much Caffeine Is In Pre-Workout?
Why Choosing The Right Pre-Workout Matters?
Choosing the right pre-workout for you and your body is crucial to prevent the formation of kidney stones.
So, what should you look for in pre-workout? When dealing with supplements, you may want to limit ingredients and find brands that are low on caffeine, proteins, or BCAAs. If you're looking for a stim-free pre-workout option, we would recommend choosing Transparent Labs Stimulant Free Pre-Workout.
Natural supplements are better for those susceptible to kidney stone infections or dehydration. Along with the right pre-workout formula, you also need to maintain a higher level of hydration to help prevent stone formation.
3 Tips On How To Prevent Kidney Stones
Kidney stone prevention should be fully discussed with your doctor before starting a supplement regimen. If you are susceptible to kidney issues, you will need to take extra precautions and maintain a more healthy diet and fitness program, including which, if any, supplements you take.
Taking pre-workout supplements has many health benefits for a durable body on a high-intensity gym routine. There can be some negative side effects, too, though. Let's take a look at how to avoid them.
1. Maintain An Active Lifestyle
Being active includes many benefits. It, for example, helps the body process and use the vitamins, minerals, and amino acids you ingest through your supplementation. If you are inactive, you won't process these compounds and chemicals properly.
Some gym goers like to take a pre-workout everyday, even on rest days. If you are prone to kidney stones, this can be a bad idea.
When you ingest high amounts of these vitamins and minerals and stay inactive, your kidneys won't be able to flush the high levels, and calcifications may form in your renal system.
Learn More - Is it Safe To Take Pre-Workout Twice A Day?
2. Hydration Levels
The only way the kidneys can remove toxins from the body is through urination. The more you can go to the bathroom, the less likely you are to form kidney calcifications. While this isn't a cure by any means, you need to stay well hydrated throughout your workout and the entire day.
For most fitness enthusiasts, 2 quarts to a gallon of water daily is recommended. However, if you are heavily supplementing or prone to kidney stones, you will need even more hydration.
It is worth bearing that you ensure you keep enough water in your system for the kidneys to function properly. Proper hydration plays a major role in kidney function, as your doctor will attest. Where your health is concerned, it isn't just what you eat but also what and how much you drink.
3. Diet & Overconsumption
A healthy lifestyle includes diet, exercise, and supplementation in moderation. Dietary practices alone are one major factor of overall health. However, the recommended doses on some supplements, like pre-workout mixes, can be adjusted.
If you aren't getting enough energy, for example, you may take a larger dose of the pre-workout drink.
While this is common and beneficial for most people, those predisposed to kidney stones may need to lower the dose. Otherwise, you raise the health risk of stone formation.
Ingesting a lot of food with artificial sweeteners, not enough vitamin C, or foods that contribute to creating high liver enzymes may all pose side effects for your kidneys, liver, and internal organs, including the build-up of masses.

Pre-Workout & Kidney Stone Common Questions
Kidney stones may not show any symptoms until they become large enough for the kidney to become damaged or blocked. The most common symptoms are severe lower back pain, nausea, vomiting, fever with or without chills, bloody urine, or frequent urination with little output.
Kidney damage, overall health, certain supplements, and elevated calcium levels are known to the endocrine society as the biggest factors.
Regular exercise alone will not cause kidney stones. On the contrary, it has shown evidence that exercise helps maintain kidney function and assists in the elimination of urea.[4] The more active you are, the better your organs, including kidneys, perform.
Some studies show that excessive amounts of creatine can lead to kidney issues, disease, or failure.[5] While the amounts vary by individual and other research is sparse, you are most likely in the clear. However, those with a predisposition to kidney problems may want to lower their creatine intake levels.
At least a couple of other factors are involved, too. High blood pressure and high liver enzymes can all have possible drawbacks when taking nutritional supplements (particularly calcium).
There are plenty of vitamins and minerals that have no ill effect on the kidneys or the formation of stones. The B-vitamin range, including B6, B12, thiamine, niacin, and riboflavin, are not harmful to people with kidney stones. B6 has also shown some promise in the reduction of oxalates in the body.[6]
Conclusion
Kidney disease, damage, and failure are major concerns for millions of people. Stones are a byproduct of damaged kidneys, dehydration, poor blood flow, and other issues. Pre-workout supplementation can aggravate these causes.
While most pre-workouts are fine to take and won't cause the formation of kidney stones in healthy individuals, it can happen.
If you are prone to kidney stones or have underlying renal issues, a natural pre-workout may be best, or none at all.
References:
1.https://rarediseases.org/rare-diseases/cystinuria/
2.https://www.renalandurologynews.com/home/news/urology/kidney-stones/calcium-and-vitamin-d-supplements-may-increase-stone-risk/
3.https://pubmed.ncbi.nlm.nih.gov/34690004/
4.https://www.webmd.com/kidney-stones/news/20131213/light-exercise-might-reduce-risk-of-kidney-stones
5.http://www.sportsci.org/jour/0001/inbrief.html
6.https://pubmed.ncbi.nlm.nih.gov/1450364/