Some subjects are taboo to speak about in public, and one of those topics happen to be bodily fluids.
When first starting a ketogenic diet, many people experience a “foaminess” to their urine, but why is this? While much of it is speculation, here’s what I’ve come to.
Why does pee look foamy on keto? Foam in the urine is usually a result of the speed of urination, dehydration, toilet chemicals, and/or protein in the urine.
In this article, I’ll discuss why you may have foamy looking urine, especially when first starting a ketogenic diet, things you should look out for that may indicate a more severe problem, and what you can do moving forward.
Table of Contents
Reasons For Foamy Urine On Keto
There are various reasons why your pee may have suddenly become foamier while following a ketogenic diet.
Assuming no other changes have been made to your lifestyle, supplementation, or additional medications, foamy pee may be attributed to the following reasons.
When first starting a ketogenic diet, many individuals will notice an increase in both the amount and frequency of urination. I wrote about it in this article here:
To elaborate a bit on why you pee more when first starting a ketogenic diet, it’s because carbohydrates help your body retain and store water.
Carbohydrates get its name from the two elements it contains carbon and hydrogen, hence “carbo” and “hydrate.”
For every gram of carbohydrate stored in your body, three grams of water will follow.
When we restrict carbohydrates from the diet, the body begins to burn through its stored glycogen (stored carbohydrates).
The average human adult will store ~500-600 grams of carbohydrates, which also means an additional ~1,500 grams of water. Combined, that’s 2kg (~4.4lbs) of water and glycogen your body is holding and gets rid of when first starting a ketogenic diet.
You may have noticed a considerable drop on the scale during the first couple of weeks, and sorry to be the bearer of bad news, but most of that was water weight.One of the potential reasons you may be experiencing foam in your urine is this increased urination, which may be causing you to pee at an increased rate, thus causing your pee to look more “foamy.”
If you’ve noticed your pee velocity has increased, this may be a contributor to why you are experiencing foamy urine.
Related to the first reason, with increased pee comes the increased likelihood of dehydration. Foamy urine can be a result of being highly concentrated.
Many people who first start a ketogenic diet find themselves dehydrated due to the increased urination, sweat, and lack of electrolytes.
When first starting a ketogenic diet, you must stay well-hydrated by drinking fluids when thirsty, but also making sure you consume adequate amounts of electrolytes.
The electrolytes sodium and potassium are especially important to be mindful of because they help your body regulate fluid balance and blood volume.
Make sure to increase sodium intake by salting your foods liberally to taste, but also get adequate amounts of potassium through keto-friendly potassium-rich foods such as avocados and green leafy vegetables.
Need an easier way to get in an adequate amount of electrolytes? Try one of these electrolyte supplements formulated with ketogenic dieters in mind.
Toilet cleaning chemicals
Have you recently changed your toilet cleaner or threw in one of those tablets in the tank of your toilet?
Some chemicals that people use to clean toilets can make the urine look foamy.
See if the problem persists after flushing or using a different toilet.
Retrograde ejaculation (for men)
When men's semen backs up into the bladder instead of being released during ejaculation, this may be a cause for foamy urine in men.
If you are noticing dry ejaculations, and this bothers you, or you are looking to conceive, please consult your doctor.
Medications to treat the pain from urinary tract infections such as phenazopyridine may be a cause for foamy urine. If you are taking one of the following drugs, this may apply:
- AZO Standard
Excreting protein part 1
One job of our kidneys is to filter extra water and waste from our blood into the urine.
If there is an underlying kidney problem, the kidneys are unable to filter as well as they should. If the kidneys are damaged, this may allow too much protein to enter the urine, known as proteinuria. *hyperlink
While not trying to cause you to worry so much, but kind of, if this is the case, it is severe and may indicate signs of chronic kidney disease or renal disease, which is the late stage of kidney damage.
*If none of the previous reasons above seem like they may be the culprit, and you’re experiencing other symptoms which I will discuss, please consult a medical professional.
Excreting protein part 2 *theory
During the initial stages of a ketogenic diet, your body undergoes increased protein breakdown.
Up until this point, your body has relied on glucose (carbohydrates) to fuel its daily needs, especially for the brain. It takes ~3 weeks for the brain to derive most of its energy from ketones.
Until this adaptation to ketones takes place, your body must convert other substrates, more specifically glycerol and protein, into glucose.
This process of converting protein in glucose is referred to as gluconeogenesis.
Gluco (glucose) Neo (new) Genesis (the formation of)
One theory is that the body is almost “wasting” additional protein and ketones during this brief period while the body is up-regulating the necessary enzymes to utilize ketones efficiently.
Increased fat *Anecdotal
After searching around some of the forums and questioning other individuals, some users experience increased foam in their urine when they raise their fat intake.
More fat = more foamy urine
While this cannot be explained scientifically, many other keto dieters have experienced this same phenomenon.
Therefore, take this with a grain of salt.
Can Ketones Cause Bubbly Urine?
In general, ketones should not be a cause of bubbles or foam in the urine.
Though, some keto dieters report a correlation between higher fat intake and more foam in their urine.
Should I Be Worried About Foamy Urine On Keto?
When looking at some of the causes for foamy urine above, try and eliminate any possible variations to figure out which may be what’s causing foamy urine for you.
Consider the most likely causes first, which are:
- Faster stream of pee
- Toilet cleaning chemicals
If none of the above causes seems logical, check the risk factors and see if you experience the accompanying symptoms below and/or if this reoccurs often.
If so, please consult a medical professional.
Other Symptoms That May Accompany Foamy Urine
The hard part about the accompanying symptoms of a more severe condition for foamy urine is trying to distinguish if it is a more serious medical problem or if you’re experiencing what people refer to as the keto flu.
I will also cover some of the risk factors that may make someone more susceptible to a more serious condition.
That being said, these are symptoms that may indicate a more serious medical condition:
- Swelling hands, feet, face, and abdomen
- Loss of appetite
Risk Factors Causing Foamy Urine
Aside from excreting water at a much higher rate at the beginning of a ketogenic diet, protein in the urine is not a good sign and may indicate potential kidney damage.
Here are some of the risk factors for kidney disease:
- Family history of kidney disease
- High blood pressure
To test for an impaired kidney, the doctor will collect a urine sample to check protein levels in the urine.
For males who may suffer from retrograde ejaculation, the doctor will check for sperm in your urine.
How Long Should Foamy Urine Last?
For those following a ketogenic diet, you may be excreting more water than usual. It's not uncommon during the first week or two after adopting a ketogenic diet to expel ~5+ lbs of water.
Try to ensure you are drinking an adequate amount of water while also increasing the amount of electrolytes sodium and potassium in your diet.
You can also supplement with additional electrolytes with supplements such as:
Is Foamy Urine Dangerous?
If the foam in the urine is due to the most likely causes, then you shouldn’t need to worry as this should generally resolve itself.
Again, the most likely causes are:
- Faster stream of pee
- Toilet cleaning chemicals
Foamy urine is usually no cause to worry, especially if you are only noticing it at the beginning of your keto journey.
Try to rule out the most likely causes first: faster stream of pee, dehydration, toilet cleaning chemical.
Some people following a ketogenic diet have also seen a relationship between the amount of fat they eat and the amount of foam in their urine, though I do not know what may cause this.
If the problem persists and you have other accompanying symptoms, this may indicate the presence of an underlying kidney problem, and you should consult a medical professional.