Lifestyle

6 Signs Your Kidneys May Be in Trouble Before You Feel Sick

By Curtis Jones · June 21, 2026

Approximately 35.5 million American adults have chronic kidney disease. Nine in ten of them don’t know it. The kidneys can lose up to 90% of their function before producing symptoms dramatic enough to send most people to a doctor. That is why kidney disease is called a silent condition — and why the signs that precede it matter so much.

1. Foamy or bubbly urine that doesn’t flush away easily

Occasional foam in the toilet is normal — it can result from a fast urine stream or minor dehydration. Persistent foam that appears consistently and takes multiple flushes to clear is a different matter entirely. It indicates protein in the urine — a condition called proteinuria — which means the kidneys’ filtering system is leaking substances it should be retaining. Proteinuria is one of the earliest laboratory markers of kidney damage and is detectable through a simple urine test long before other symptoms appear.

2. Swelling in the ankles, feet, hands, or around the eyes

Healthy kidneys remove excess fluid from the body. When they can’t, fluid accumulates in the tissues — most visibly in the lower extremities, hands, and the area around the eyes, particularly in the morning. If you notice puffiness around your eyes when you wake up, or if your shoes feel tighter than usual by the end of the day without explanation, the swelling may reflect fluid retention caused by declining kidney function. The pattern is typically gradual — which is why people attribute it to salt intake, standing too long, or aging before considering their kidneys.

3. Fatigue that doesn’t improve with rest

Kidneys produce erythropoietin — a hormone that signals the bone marrow to make red blood cells. When kidney function declines, erythropoietin production drops, red blood cell count falls, and oxygen delivery to muscles and organs decreases. The result is a persistent, systemic fatigue that doesn’t improve with sleep and doesn’t respond to caffeine. People describe it as feeling drained at a level deeper than ordinary tiredness. It is frequently diagnosed as depression or chronic fatigue before kidney function is checked.

4. Persistent itchy, dry skin

The connection between skin and kidneys is not intuitive, but it is direct. When kidneys cannot properly filter waste and maintain mineral balance in the blood, toxins accumulate and the resulting imbalance can produce persistent itching and dry skin that doesn’t respond to moisturizers or topical treatments. The itching tends to be generalized rather than localized — it doesn’t feel like a rash or an allergic reaction. It feels like it comes from beneath the skin.

5. Changes in urination frequency or color

Any sustained change in urination patterns deserves attention. Needing to urinate significantly more often — especially at night — or producing urine that is darker than usual, pinkish, or reddish can indicate blood in the urine. A decrease in urine output despite normal fluid intake is also significant. None of these changes are diagnostic on their own, but any persistent shift from your normal pattern warrants mention to your doctor.

6. Muscle cramps, especially at night

Kidneys regulate electrolyte balance — including calcium, potassium, and sodium. When that balance is disrupted by declining kidney function, muscle cramps can result. Frequent leg cramps at night, particularly when not explained by exercise or dehydration, can be an early indicator of the mineral disturbances that accompany kidney disease. The cramps are often dismissed as normal aging or insufficient stretching.

The screening is simple and available at any primary care visit: an eGFR blood test and a urine albumin-to-creatinine ratio. Together they take minutes and can detect kidney disease years before symptoms appear. People with diabetes, high blood pressure, a family history of kidney disease, or who are over 60 should be screened regularly. If you’ve never been tested, ask at your next appointment.