More than 35 million American adults are living with chronic kidney disease, and roughly 9 in 10 of them have no idea, according to the National Institute of Diabetes and Digestive and Kidney Diseases. The reason is simple. Early kidney damage rarely announces itself. It shows up as vague tiredness, an odd change in the bathroom, a bit of puffiness in the morning, all easy to shrug off as poor sleep or getting older.
Kidneys filter about a half-cup of blood every minute, and they can lose a lot of function before anything feels clearly wrong. The National Kidney Foundation lists a set of quiet warning signs worth paying attention to, especially for anyone with diabetes, high blood pressure, heart disease, obesity or a family history of kidney failure.
Here are nine of them, in plain language.
The 9 signs to know
1. Foamy urine. Not a couple of bubbles that fade, but persistent foam that lingers in the bowl. The National Kidney Foundation says that "lots of bubbles or foam in your urine, especially if it happens often," can signal protein leaking through damaged kidney filters.
Also read: Hidden heart threat affects one in five: Why standard blood tests miss it
2. Blood in your urine. Pink, red or cola-colored urine can mean the filters are letting red blood cells slip through. It also has other causes, from infections to stones, so it needs to be checked promptly.
3. Needing to pee more often, especially at night. Damaged nephrons, the kidney's filtering units, may struggle to concentrate urine, so you make more of it and get up during the night.
4. Swollen ankles and feet. When the kidneys can't clear enough fluid and sodium, gravity pulls the excess into the lower legs. Shoes feel tight by evening, and a fingertip press leaves a dent.
5. Puffy eyes in the morning. Protein loss in the urine changes how fluid moves through the body, and one early sign is swelling around the eyes on waking.
Also read: What eating too much salt every day can do to your body - beyond blood pressure
6. Feeling tired all the time. As kidney function drops, waste builds up in the blood and the body produces less erythropoietin, a hormone that tells bone marrow to make red blood cells. The result is anemia and a heavy, drained kind of fatigue that sleep does not fix.
7. Trouble sleeping. Toxin buildup and a higher rate of sleep apnea in people with kidney disease can make it hard to fall or stay asleep.
8. Poor appetite and a metallic taste. Uremic toxins can dull hunger and change how food tastes, so meals become less appealing and unexplained weight loss can follow.
9. Dry, itchy skin. Advanced kidney disease throws off the balance of minerals like phosphorus and calcium, which can leave skin persistently itchy or rough.
Also read: Doctor reveals the overlooked cause of knee and hip pain
When to see a doctor
Any single sign on its own is usually something else. Several at once, or one that lingers, is worth a conversation with a primary care doctor, especially with a known risk factor in the picture. The National Kidney Foundation and NIDDK both recommend routine screening for adults with diabetes, high blood pressure, heart disease, obesity or a family history of kidney disease.
Screening is not complicated. It takes two tests, both widely available. The eGFR, a blood test that estimates how well the kidneys filter, and the uACR, a urine test that looks for small amounts of albumin, a protein that should stay in the blood. Together they can catch kidney damage years before symptoms make it obvious.
Age matters too. The American Kidney Fund reports that chronic kidney disease affects about 34 percent of Americans 65 and older, and that Black, Hispanic and Native American adults face substantially higher rates of kidney failure than white adults.
Chronic kidney disease is not reversible once it takes hold, but progression can often be slowed with treatment of blood pressure, blood sugar and the underlying causes. Catching it early is the part that changes the outcome.
Also read: The brain chemical that spikes during exercise may protect your memory for decades
Also read: Coach says these habits lead to greater confidence
This article is made and published by Jesper Bengtson, who may have used AI in the preparation.