Top questions about kidney disease answered

Kidney disease might not be something we often think about, but it is actually one of the leading causes of death worldwide. According to the National Kidney Foundation, about 10 percent of people globally suffer from chronic kidney disease (CKD), and millions lose their lives to it each year. The main job of kidneys is to remove toxins and excess water from the blood. They also help control blood pressure and even keep your bones strong. When they are damaged, they cannot do these jobs properly, leading to kidney disease. In fact, if you have diabetes or high blood pressure, you are more likely to develop kidney problems. Also, if any kidney disease progresses to failure, treatments like dialysis or even a transplant may be needed. If you want to know more about kidney diseases, we have answers from India’s top nephrologist.

Common questions about kidney diseases

On World Kidney Day 2025, Health Shots interviewed nephrologist Dr Bharat Shah, who has more than 30 years of experience. He answered some of the most common questions about kidney diseases to help us all better understand kidney health and how it functions.

Question 1: About 9 in 10 adults with kidney disease do not even know they have it. So, what are the common signs that might point to kidney disease?

Dr Bharat Shah: Kidney disease often does not show symptoms in its early stages, which is why so many people are unaware they have it. However, if the disease progresses or is not managed properly, you might start noticing some symptoms, including:

• Unexplained weight loss and loss of appetite
• Swelling in your ankles, feet, or hands due to water retention
• Shortness of breath
• Persistent tiredness
• Blood in your urine
• Frequent need to urinate, especially at night
• Difficulty sleeping
• Itchy skin
• Muscle cramps
• Feeling nauseous or sick
• Headaches
• Erectile dysfunction in men

It is important to have regular checkups, as early diagnosis can help prevent the disease from worsening. If you notice any of these symptoms, be sure to consult a doctor for further evaluation.

Question 2: Kidney disease is one of the leading causes of death worldwide. So, what are the most common causes?

Dr Bharat Shah: That is right. Kidney disease is a major health concern, as per the World Health Organization. The most common causes are long-term diabetes and uncontrolled high blood pressure, especially when these conditions go untreated for years. Other causes include conditions like Glomerulonephritis (inflammation of the kidney’s filtering units), kidney stones, drug-induced kidney damage, and kidney cysts. Over time, these conditions can lead to chronic kidney disease (CKD) and, eventually, kidney failure. Poor lifestyle choices, like an unhealthy diet, lack of exercise, and smoking, can also raise your risk of developing kidney problems.

Question 3: Who is at risk for chronic kidney disease (CKD), and what are some complications?

Dr Bharat Shah: Several factors can put you at a higher risk for CKD. If you have diabetes, high blood pressure, heart disease, or a family history of kidney issues, your chances of developing CKD increase. Additionally, being obese, smoking, or following an unhealthy diet can also raise the risk. Age is another factor—your risk goes up as you get older. If your kidneys are not functioning well, it can lead to complications like anemia, weak bones, fluid retention, gout, heart disease, and high blood pressure. Managing these risk factors early can help reduce the chances of developing CKD and its complications.

Question 4: What are the different types and causes of kidney disease?

Dr Bharat Shah: Kidneys play a crucial role in filtering out waste and excess fluid from our blood, which is why we cannot live without them. There are several types of kidney diseases, each with different causes and effects. Some of the most common ones include:

• Chronic kidney disease (CKD): A long-term condition where the kidneys gradually lose their function.
• Kidney stones: Hard deposits that form in the kidneys and can cause severe pain.
• Glomerulonephritis: Inflammation of the kidney’s filtering units, which can affect kidney function.
• Polycystic kidney disease: A genetic condition where fluid-filled cysts grow in the kidneys.
• Urinary tract infections (UTIs): Infections that can spread to the kidneys if left untreated.
• Kidney failure: When the kidneys stop working entirely and dialysis or a transplant is needed.

Question 5: How can diabetes damage the kidneys?

Dr Bharat Shah: Diabetes is actually the leading cause of kidney disease. Around 1 in 3 adults with diabetes develop kidney problems, according to the National Institute of Diabetes and Digestive and Kidney Diseases. High blood sugar levels from poorly controlled diabetes can damage the tiny blood vessels in the kidneys, making it harder for them to filter waste. Over time, this damage can lead to a condition called diabetic nephropathy, where the kidneys slowly lose their ability to function properly. If diabetes is not well managed, it can progress to kidney failure, and treatments like dialysis or a kidney transplant may be needed.

Question 6: What are the risks of untreated kidney disease?

Dr Bharat Shah: If it is not treated, it can advance to kidney failure, which requires treatments like dialysis or a transplant. But it does not stop there—untreated kidney problems can also increase the risk of other serious conditions like cardiovascular disease, high blood pressure, and even worsening diabetes. The key to managing kidney disease is early detection and regular monitoring, which can help prevent complications and keep the kidneys functioning as well as possible.

Question 7. What types of tests can help diagnose kidney disease?

Dr Bharat Shah: The tricky thing about kidney disease is that many people do not realize they have it until it has already progressed because there are often no noticeable symptoms in the early stages. This is why regular testing is so important, especially if you are at higher risk due to factors like diabetes, high blood pressure, or a family history of kidney problems. To diagnose kidney disease, doctors typically use blood tests, like the serum creatinine test, to check how well your kidneys are working. Urine tests can also help by looking for protein or blood in your urine, which are signs of kidney damage. Additionally, imaging tests like ultrasounds or CT scans can give doctors a closer look at kidney health and any abnormalities.

Question 8. What happens if kidneys fail to function?

Dr Bharat Shah: Kidney failure, or end-stage renal disease (ESRD), is a serious condition that occurs when the kidneys can no longer filter waste, remove excess fluid, or balance your body’s electrolytes effectively. When this happens, toxins build up in the body, which can cause symptoms like swelling, fatigue, shortness of breath, and confusion. Kidney failure also puts you at a higher risk of heart disease and stroke. According to the National Kidney Foundation, other complications that can arise from kidney failure include:

• Anemia (low red blood cell count)
• Metabolic acidosis (an imbalance of acid in the blood)
• Mineral and bone disorders (which can affect your bones and heart)
• Hyperkalemia (high potassium levels in the blood)

If kidney failure occurs, there are two main treatment options: dialysis, which helps filter your blood artificially, or a kidney transplant, where a healthy kidney from a donor is transplanted into your body.

Question 9: One in ten people is affected by chronic kidney disease (CKD), and millions die annually from it. Is it possible to prevent kidney disease?

Dr Bharat Shah: Yes, kidney disease can often be prevented, or at least its progression slowed, by making some simple but impactful lifestyle changes. The key is managing conditions like diabetes and high blood pressure, staying active, eating a kidney-friendly diet, and avoiding smoking. Here are some tips you can follow to prevent CKD:

• Lose weight if you are overweight or obese.
• Stay active, as regular exercise helps control blood sugar levels.
• If you smoke, quitting is one of the best things you can do for your kidney health.
• Take your prescribed medications as directed.
• Keep your cholesterol levels in check.
• Reduce your salt intake and focus on eating more fruits and vegetables.
• Limit alcohol consumption, as it can raise blood pressure.
• Make sure to get your flu shot every year—people with CKD are at higher risk for severe flu complications.
• Small changes like these can make a big difference in your kidney health over time.

Question 10. What is a kidney-friendly diet?

Dr Bharat Shah: A kidney-friendly diet focuses on foods that reduce the strain on your kidneys. This includes low-sodium, low-protein, and low-potassium foods. Vegetables like cauliflower, bell peppers, and cabbage, along with fruits like apples, berries, and grapes, are great options. Whole grains like oats and quinoa provide fibre without overwhelming the kidneys. Avoid high-sodium foods like processed snacks and canned soups, and reduce protein intake, especially from animal sources.

Now that you have the answers to all the important questions about kidney diseases, make sure you take care of your kidneys and overall health.