by When it comes to health, most of us don’t think twice about a quick trip to the bathroom. But scientists in Sweden say a surprising sign in your pee could reveal much more than you realize — including your risk of dementia.
A large study from the Karolinska Institute followed more than 130,000 adults over 65 in Stockholm who had no dementia at the start. Within just four years, 7% of participants developed the disease. The researchers discovered that people with higher levels of albumin in their urine — a condition called albuminuria — had a significantly greater chance of developing dementia later in life.
What Does Foamy Pee Have to Do With the Brain?
If you’ve ever noticed your urine looking bubbly or foamy (like the top of a beer), doctors say it could be a red flag. That frothiness often points to albumin being present in your urine — meaning your kidneys may be leaking protein.
Researchers made the link between urine and dementia (Getty Stock)
Dr. Hong Xu, assistant professor in neurobiology at Karolinska, explained why this matters:
“The kidneys and the brain may seem like very different organs, but they share an important characteristic: both depend on a delicate network of small blood vessels. When the blood vessels in the kidneys are damaged, the same process often occurs in the brain.”
This damage to blood vessels is one of the main drivers of vascular dementia, the second most common form of dementia.
How Much Does It Raise the Risk?
- People with moderate albumin levels (30–299 mg/g) had a 25% higher risk of developing dementia.
- Those with higher levels (300 mg/g or more) faced a 37% higher risk.
While that doesn’t mean everyone with foamy urine will go on to develop dementia, the researchers stress that it’s an early warning sign worth paying attention to.
Symptoms of Albuminuria You Shouldn’t Ignore
According to Alzheimer’s Research UK and the National Kidney Foundation, common signs include:
If you have albuminuria, you could have dementia when you’re older (Getty Stock)
- Foamy urine
- Frequent urination
- Puffy eyes
- Swelling in feet, ankles, or face
If you notice these changes, it may be worth speaking to a doctor and asking about a simple urine test.
Why Early Detection Matters
The study, published in the Journal of Internal Medicine, highlights the importance of routine kidney screenings, especially for people with high blood pressure, diabetes, cardiovascular disease, or existing kidney problems.
Dr. Xu believes that spotting albuminuria early could give doctors the chance to protect both kidney and brain health. In her words:
“Early detection of albuminuria could potentially delay or prevent the onset of dementia.”
Bottom Line
That extra foam in the toilet bowl may not just be harmless bubbles. While sometimes caused by dehydration or a heavy protein meal, it could also be an early sign that your kidneys — and possibly your brain — need attention.
Taking a proactive approach by getting regular check-ups could help lower your risks and protect your long-term brain health.
For more resources on dementia, visit the Mayo Clinic’s dementia guide.
