This information is provided as general information and not as specific medical advise. As always, if you have concerns about your health, please consult with your doctor or other qualified medical provider.
One of the more common questions that I’ve heard from people starting a ketogenic or low carbohydrate diet is why they get foamy urine on a ketogenic diet. Foamy keto urine is usually caused by either increased urine stream, concentrated urine from dehydration, excess protein, or certain medications.
Foamy Keto Urine Cause #1 – More urine
One common cause of foamy keto urine is too much urine. If you’re just starting the keto diet, one thing a lot of people notice is that they are peeing more frequently. The increased urination is from two reasons.
First, as you go onto a low carb diet, your body may deplete its stored glucose (glycogen). Since each gram of glycogen is stored with four grams of water, your body needs to get rid of the excess water, and that’s mostly going to be by making more urine.
Second, most people on a ketogenic diet also will be drinking more water and other fluids throughout the day to avoid the “keto flu” and this extra intake of fluids is going to end up as urine later in the day.
The higher volume of urine in the bladder can increase the force and volume of the urine and cause the urine to foam when it hits the toilet bowl.
Foamy Keto Urine Cause #2 Dehydration
Just like too much water can cause foamy keto urine, too little water and letting yourself get dehydrated can also cause your pee to foam in the toilet bowl. If you’re dehydrated, your urine is more concentrated with waste products from your kidneys and this can also cause your urine to foam temporarily.
The simple solution to this cause of foamy keto urine is to remember to increase your fluid intake while on the ketogenic diet, especially during the first couple of weeks. It’s also important to make sure you’re getting enough electrolytes such as sodium, potassium and magnesium.
Check out our Ketogenic Diet Mistakes to Avoid article
Foamy Keto Urine Cause #3 – Excessive Protein
Too much protein in your diet may also cause foamy keto urine. A well-formulated ketogenic diet should be about 70% fat, 20-25% protein, and 5 to 10% carbohydrates. But many times, people on a keto diet have a much higher protein intake and a lower fat intake. On a higher protein diet, your body will break down some of the excess protein into urea, which your kidneys will then filter and excrete the extra urea into your urine. If you decrease your protein, you should see less foamy urine.
Foamy Keto Urine Cause #4 – Certain medications
Believe it or not, certain medications can cause your urine to foam while you’re taking them. The medication that most commonly cause your pee to foam is phenazopyridine (also know as Azo or pryidium) which is used to relieve the spasm and pain from bladder infections. This medicine will also turn your urine an orange color while taking it. Both the foamy urine and the orange color should resolve once you stop taking the medication.
Foamy Keto Urine Cause #5 – Urinary tract infections
If you are having pain, discomfort, or blood in your urine with the foaming urine, you might also have a bladder infection, so see your doctor if there is a concern about a urinary tract infection. Bladder or kidney infections may also have foul-smelling urine.
Foamy Keto Urine Cause #6 – Prostate issues in men
In men, the urethra passes thru the prostate, and prostate issues like an enlarged prostate can cause the urine to foam because it may restrict the urine flow. Men may also notice foamy urine after ejaculation from prostatic fluid. If you’re an older male noticing a progressive issue with your urinary stream, it may be time to let your doctor know.
Some men with prostate issues may experience a condition known as retrograde ejaculation when they ejaculate. In these cases, the sperm and prostatic fluid ends up in the bladder and mixes with urine, and can then result in foamy urine.
Foamy Keto Urine Cause #7 – Too much fat
Some people claim that they noticed foaming urine on a ketogenic diet when they increase their fat intake and their blood ketone levels go higher. It’s unclear if its the excess fat or the kidneys excreting ketones in the urine that cause the foaming urine. But dropping your fat intake a little may help stop the foaming urine.
Foamy Keto Urine Cause #8 – Chemicals in the toilet
Believe it or not, some toilet chemicals used to keep your toilet clean can also foam as well when you use the toilet.
Foamy Keto Urine Cause #9 – Other medical problems
When to worry about foamy urine
If you occasionally have foamy urine and no other medical problems, its not something that you have immediately see your doctor. However, if you consistently notice that your urine is foaming for longer than a week or two, you should at least discuss it with your doctor.
Often times a simple urine test can rule out protein, glucose, and/or blood in the urine that could mean there’s an underlying medical condition causing the foamy urine and that it’s not due to a ketogenic diet.
Diabetes and underlying kidney diseases from either long-standing high blood pressure or an autoimmune disease that affects the kidneys are several medical conditions that may need to be ruled out.
Diabetes and foamy urine
If you have poorly controlled diabetes and high blood glucose, you will usually get glucose in your urine as well. A
Kidney disease and foaming urine
If you have a history of kidney disease or underlying kidney problems, let your doctor know if you are experiencing foamy urine since this symptom could mean your kidneys are having a harder time with filtering protein and excreting the protein in your urine.
People with new-onset kidney problems may have other symptoms like nausea, muscle pains and excessive fatigue.
If in doubt, check with your doctor.
Kidney Stones or Kidney Injury
Kidney stones or a kidney injury can also be another cause of foaming urine or bubbly urine.
Kidney stones may also have blood in urine or kidney pain or bladder pain. Bladder or kidney infections may also have foul-smelling urine.
A kidney injury from a fall or car accident can also cause foaming urine bubbles in some cases.
If you notice a change in the color of your urine, such as dark urine color instead of light yellow urine, that may be another sign of underlying kidney issues. Cloudy urine can also be a sign of kidney infection or other kidney problems and should be a reason to see your doctor
High blood pressure and foaming urine
Long standing high blood pressure can cause damage to your kidneys and affect the kidneys’ ability to filter protein and other waste products. If you have a history of high blood pressure, you should check with your doctor if you notice that your urine is starting to foam. The foamy urine may be a hint that your blood pressure is not under control and that your kidneys are having problems with your high blood pressure.
The good news is that many people that follow a low carbohydrate diet lose a significant amount of weight and this weight loss helps with reducing high blood pressure.