Even if you never hold in your urine, you can still develop kidney disease—or even kidney cancer—if you regularly do the following six things.

The kidneys act as the body’s central “waste treatment plant,” regulating fluids, electrolytes, and acid–base balance to sustain life. However, according to WHO data, chronic kidney disease is now the 10th leading cause of death globally, with around 1.2 million deaths each year. As for kidney cancer, GLOBOCAN 2022 reported more than 155,000 new deaths worldwide.

Many people assume that holding in urine is the most harmful habit for the kidneys, but in reality, there are other hidden culprits. To protect this vital “filter,” doctors warn you to change these six dangerous habits immediately:

1. A diet high in salt and salty seasonings

Hidden salt in processed and packaged foods is a silent threat that can quickly damage the kidneys.

Excess salt increases sodium levels in the blood, causing fluid retention and high blood pressure. This forces the kidneys to work under high filtration pressure, damaging kidney tubules and glomeruli. Over time, this can lead to proteinuria and chronic kidney failure.

2. Overuse of medications and supplements

Many people blindly trust “kidney supplements” or take health products without medical guidance. Overconsumption of these substances can lead to drug-induced kidney disease.
Certain painkillers and nonsteroidal anti-inflammatory drugs (NSAIDs), when used long-term, can directly harm the kidneys, causing acute injury or permanent failure.

3. Excess intake of fat, sugar, and animal protein

Too much protein—especially animal protein—puts continuous strain on the kidneys, leading to glomerular damage.
Excess sugar increases metabolic burden and can lead to diabetic kidney disease.
Meanwhile, high fat intake contributes to obesity and high blood pressure, accelerating kidney aging and decline.

4. Chronic sleep deprivation and overwork

Staying up late reduces the kidneys’ ability to repair themselves. Long-term lack of sleep weakens the immune system, increasing the risk of kidney infections.
Chronic stress disrupts hormones and overactivates the adrenal glands, damaging kidney function from within.

5. Drinking too little water

Water is essential for flushing out toxins. Dehydration leads to concentrated urine, making it harder for the kidneys to eliminate waste.
This increases the risk of kidney stones and toxin buildup.
Doctors recommend adults drink about 1.5 to 2.5 liters of water daily to maintain stable filtration and protect kidney cells.

6. Smoking and excessive alcohol consumption

This is a “double hit” to kidney blood vessels. Nicotine causes blood vessels to constrict, reducing blood flow to the kidneys.
Alcohol impairs metabolism, leading to toxin buildup and reduced detoxification capacity.
Over time, these habits can directly lead to rapid and irreversible kidney failure.

Tips for protecting your kidneys

The kidneys are delicate and easily damaged by poor diet and lifestyle habits. To reduce the burden on them, doctors recommend maintaining a balanced, low-salt diet and limiting processed foods to control blood pressure and filtration stress.

Drink enough water daily and include light, low-potassium fruits and vegetables to support natural detoxification without increasing the risk of stones.
Reducing animal protein and replacing it with fish or plant-based protein can help prevent kidney damage and preserve long-term function.
If you notice swelling or abnormal urine, you should get your kidney function checked promptly.