Expert urges 4.6 million Koreans with chronic kidney disease to break 3 small habits

About 4.6 million Koreans now have chronic kidney disease, with cases more than doubling over the past decade, according to this year's data from the Korean Society of Nephrology.

What daily habits put our kidneys at risk? Are there ways one can protect them in everyday life?

Professor Jung Chan-young of Asan Medical Center said on the hospital’s YouTube channel, "Minor, unhealthy lifestyle habits can harm kidneys. In severe cases, dialysis or transplantation may be needed. Once damaged, kidneys are hard to restore, so protecting them with healthy daily habits is crucial."

The first daily habit that can harm kidney health is not drinking enough water.

Professor Jung said, "The kidneys produce urine to expel waste. Water is vital for this process. Without enough, waste isn’t diluted well, and urine becomes concentrated. This can damage the kidneys' tiny tubes and, in worse cases, cause kidney stones."

The kidneys need enough water to flush out waste, so proper intake is essential. How much and how often should you drink?

Professor Jung advised, “For healthy kidneys, it's good to drink 1.5 to 2 liters of water a day. It's important to develop the habit of drinking water regularly, even when you don't feel thirsty. Also, it's better to drink water frequently throughout the day in small amounts rather than drinking a large amount all at once."

About six or seven cups a day is recommended, and there's a simple way to check if it's enough.

“When your urine appears light yellow or almost transparent, it's a sign you're adequately hydrated,” Professor Jung explained.

Another small daily habit that damages the kidneys is consuming too many salty foods. Salty foods—meaning those high in sodium—are particularly harmful to the body, especially the kidneys, and there's a reason for this.

Consuming too much salt causes our bodies to retain more water, which can elevate blood pressure. “This resulting hypertension is one of the kidneys' greatest enemies. Hypertension puts pressure on and damages the small blood vessels, impairing their filtering function. If left untreated, it can prevent the kidneys from functioning properly,” Professor Jung said. “Ultimately, the small blood vessels in the kidneys become damaged when continuously exposed to high blood pressure.”

To keep your kidneys healthy, limit daily salt intake to about 5–6 g (about one teaspoon). Professor Jung Chan-young explained, “You can simply reduce the number of times you eat soups, stews, and instant noodles during the week compared to now. Additionally, processed foods, fast food, instant meals, and pickled foods are high in salt, so try to avoid them as much as possible. When cooking, using herbs or spices instead of salt can enhance flavor while reducing salt intake.”

Frequent and indiscriminate use of medications, especially painkillers, is a third habit that can damage the kidneys.

Professor Jung said, "Painkillers for headaches or muscle pain, especially NSAIDs like ibuprofen and naproxen, strain the kidneys. Even cold medicines can contain nonsteroidal anti-inflammatories."

Professor Jung added, "Supplements like Gongjindan, herbal medicines, or milk thistle can benefit health if taken properly, but indiscriminate use burdens the kidneys."

So, exactly how do these substances damage the kidneys? Professor Jung explained, “Long-term or excessive misuse can reduce renal blood flow and damage kidney tissue. When the kidneys are continuously exposed to harmful drugs, the damage accumulates gradually and can eventually lead to serious problems.”

To maintain healthy kidneys, avoid taking medications like painkillers long-term without consulting a specialist. Jung said, "If you have pain, first try rest, cold, or warm compresses. Only use painkillers if needed, at the proper dosage, and for the shortest time. If taking several medicines, consult your doctor or pharmacist."