Kidney health: functions, risks and tips for prevention.
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The kidneys are one of the central organs in the human body. They are not only responsible for cleansing the blood of waste products, but also regulate the water balance, ensure electrolyte balance and are involved in blood pressure control. Without these vital processes, many bodily functions would quickly become unbalanced, which could lead to serious health problems.
Where are the kidneys located?
The kidneys are located on both sides of the spine at the back of the abdomen, below the rib cage. The right kidney lies slightly lower than the left due to the position of the liver. This protected position offers the kidneys natural protection from injury and pressure.
The kidneys are closely connected to the urinary system. Each kidney is connected to the bladder via ureters, through which the filtered urine is passed.
The kidneys are closely connected to the urinary system. Each kidney is connected to the bladder via ureters, through which the filtered urine is passed.
The anatomy of the kidneys.
The anatomy of the kidneys not only explains their location in the body, but also their complex structure and the way their filtering system works. This structure enables the kidneys to fulfil their vital tasks efficiently.
How do the kidneys work?
The kidneys are the body's central filter system. Their main task is to cleanse the blood of waste products and toxins and excrete them via the urine.
The kidney consists of millions of tiny filter units, the so-called nephrons, which are responsible for blood purification. Each nephron contains a small ball of capillaries called the glomerulus. This is where waste products and excess water are filtered out of the blood and drained via the renal tubules, where useful substances such as water or electrolytes are returned to the body as required.
The kidney consists of millions of tiny filter units, the so-called nephrons, which are responsible for blood purification. Each nephron contains a small ball of capillaries called the glomerulus. This is where waste products and excess water are filtered out of the blood and drained via the renal tubules, where useful substances such as water or electrolytes are returned to the body as required.
Side facts about the function of the kidneys:
- Blood flow: Around 1.2 litres of blood flow through the kidneys every minute, which accounts for around 20-25% of the total cardiac output. This shows how central the kidneys are to maintaining blood circulation. This means that around 1,500 litres of blood flow through the kidneys every day.
- Urine production: The kidneys produce an average of around 1 to 2 litres of urine per day, depending on fluid intake and other individual factors.
- Detoxification: The kidneys filter around 180 litres of fluid every day, most of which is water and most electrolytes are returned to the body. Only about 1-2 litres are excreted as urine.
- Number of nephrons: Each kidney contains around 1 million nephrons, which act as miniature filtration systems. Together they enable the filtering of blood and the production of urine.
- Recovery of important substances: The kidneys not only filter waste products, but also retain useful substances such as water, salts and glucose when the body needs them.
- Acid-base balance: The kidneys play an important role in regulating the acid-base balance by removing excess acids from the body and stabilising the pH balance in the blood.
Can you live with one kidney?
Yes, people can easily live with just one functioning kidney. Many people are even born with only one kidney, while others lose or donate a kidney due to illness or accident.
The remaining kidney usually takes over the full function and compensates for the loss of the other kidney. It often grows slightly larger to cope with the extra work.
With a healthy lifestyle, which includes a balanced diet, regular check-ups and sufficient fluid intake, you can lead a normal and healthy life with one kidney, but it is important to protect the remaining kidney, as any additional stress (e.g. high blood pressure, diabetes) increases the risk of kidney problems.
The remaining kidney usually takes over the full function and compensates for the loss of the other kidney. It often grows slightly larger to cope with the extra work.
With a healthy lifestyle, which includes a balanced diet, regular check-ups and sufficient fluid intake, you can lead a normal and healthy life with one kidney, but it is important to protect the remaining kidney, as any additional stress (e.g. high blood pressure, diabetes) increases the risk of kidney problems.
Living with only one kidney: What should you consider?
- Regular medical check-ups: It is important to have your kidney function checked annually to ensure that the remaining kidney continues to work well and shows no signs of overload.
- Adequate fluid intake: Drink enough water to support kidney function and efficiently flush waste products from the body.
- Control blood pressure: High blood pressure can put a strain on the kidneys. Keep blood pressure in the normal range through a healthy diet, exercise and, if necessary, medication.
- Avoid certain medications: Some medications, such as non-steroidal anti-inflammatory drugs (NSAIDs), can damage the kidneys. It is advisable to consult a doctor before taking painkillers or other medications.
- Balanced diet: A diet that is low in salt and saturated fats contributes to overall kidney health and reduces the risk of high blood pressure or diabetes.
What kidney diseases exist?
There are various kidney diseases that can affect the health and function of the kidneys. These diseases range from acute infections to chronic kidney weakness and should be recognised and treated at an early stage.
How do you even realise that your kidneys are diseased?
Kidney disease often manifests itself through various symptoms that can easily be overlooked. The most common signs include:
- Changes in urine: A change in the colour, amount or frequency of urination (e.g. foamy urine, frequent urge to urinate at night).
- Swelling (oedema): Especially in the feet, ankles or around the eyes. This is an indication that the kidneys are not excreting fluids effectively.
- Lower back pain: Pain or discomfort in the kidney area may indicate inflammation or kidney stones.
- Fatigue and weakness: As the kidneys play a role in the production of red blood cells, kidney dysfunction can lead to anaemia, which causes fatigue.
Kidney inflammation
Kidney inflammation (nephritis) is often caused by bacterial infections or autoimmune diseases. They can impair the filter function of the kidneys and lead to symptoms such as fever, back pain and changes in the urine.
Causes
Bacterial infections, especially after untreated urinary tract infections, as well as autoimmune diseases such as lupus.
Symptoms
Fever, back pain, cloudy urine, reduced urine output.
Treatment
Antibiotics to fight the infection, rest, and in more severe cases corticosteroids to suppress the immune system in autoimmune diseases.
Kidney stones
Kidney stones occur when minerals and salts crystallise in the urine and form stones. These can be painful and block the flow of urine.
Causes
Insufficient fluid intake, a diet rich in oxalates (e.g. spinach), and genetic predisposition.
Symptoms
Severe pain in the back or side, blood in the urine, nausea and vomiting.
Treatment
Small stones can often be eliminated by drinking more water. Larger stones may require shock wave therapy or surgery.
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Renal insufficiency (kidney weakness)
Renal insufficiency occurs when the kidneys can no longer fulfil their function adequately. It can be acute or chronic and lead to an accumulation of waste products in the blood.
Acute vs. chronic
Acute renal failure occurs suddenly, often as a result of dehydration, infection or medication. Chronic renal failure develops over months or years and is often a result of diabetes or high blood pressure.
Symptoms
Fatigue, swelling in the legs and feet, shortness of breath, reduced urine production.
Treatment
In the early stages, the insufficiency can be treated with medication and diet management. In advanced stages, dialysis or a kidney transplant is required.
Pyelonephritis (inflammation of the renal pelvis)
Pyelonephritis is a bacterial infection that affects the renal pelvis and often develops from an untreated bladder infection. It usually requires immediate medical treatment to prevent kidney damage.
Causes
Often caused by bacteria rising from the bladder, typically after a urinary tract infection.
Symptoms
Fever, severe pain in the lower back or side of the abdomen, nausea and vomiting.
Treatment
Antibiotics are usually administered. In severe cases, hospitalisation may be necessary to monitor the infection.
Kidney cysts
Renal cysts are fluid-filled sacs that can form in the kidneys. They are often harmless (simple), but sometimes they can occur in connection with a disease such as polycystic kidney disease.
Causes
Often age-related or genetic (as in polycystic kidney disease).
Symptoms
In most cases, simple cysts do not cause any symptoms. However, larger cysts can cause pain, high blood pressure or reduced kidney function.
Treatment
Kleine, einfache Zysten erfordern keine Behandlung, außer regelmäßige Kontrolle. Bei größeren oder problematischen Zysten kann eine Punktion oder Operation notwendig sein.
How are kidney diseases treated?
The treatment of kidney disease depends on the specific disease and the progression of the disease. Common treatment approaches include:
Medication
In the case of kidney infections, antibiotics are often used to fight the infection and prevent damage to the kidneys. Blood pressure lowering medication is also important to reduce pressure on the kidneys, as high blood pressure is one of the main causes of kidney failure. In addition, electrolyte balancing medications help to keep sodium, potassium and calcium levels in balance.
Lifestyle changes
A low sodium diet and adequate fluid intake can help support kidney function. Regular check-ups make it possible to recognise abnormalities at an early stage and prevent the progression of diseases.
In the case of kidney infections, antibiotics are often used to fight the infection and prevent damage to the kidneys. Blood pressure lowering medication is also important to reduce pressure on the kidneys, as high blood pressure is one of the main causes of kidney failure. In addition, electrolyte balancing medications help to keep sodium, potassium and calcium levels in balance.
Lifestyle changes
A low sodium diet and adequate fluid intake can help support kidney function. Regular check-ups make it possible to recognise abnormalities at an early stage and prevent the progression of diseases.
Dialysis
In cases of severe kidney failure, dialysis is used to cleanse the blood. This is done either by haemodialysis using a machine or peritoneal dialysis in the abdomen. Both methods are vital if the kidneys have lost their function.
Kidney transplantation
Kidney transplantation is the long-term solution for chronic kidney failure. It restores kidney function by using a healthy kidney from a donor. A successful transplant significantly improves quality of life, but requires lifelong medication to prevent rejection.
In cases of severe kidney failure, dialysis is used to cleanse the blood. This is done either by haemodialysis using a machine or peritoneal dialysis in the abdomen. Both methods are vital if the kidneys have lost their function.
Kidney transplantation
Kidney transplantation is the long-term solution for chronic kidney failure. It restores kidney function by using a healthy kidney from a donor. A successful transplant significantly improves quality of life, but requires lifelong medication to prevent rejection.
How does cold affect the kidneys?
Cold weather can have indirect effects on the kidneys by increasing the risk of infection and inflammation. In cold weather, people tend to drink less water, which can affect kidney function. Cold weather can also increase blood pressure, which puts additional strain on the kidneys.
Cold weather weakens the immune system, which increases the risk of urinary tract infections (which can lead to kidney inflammation) and cold weather also causes blood vessels to contract, which increases blood pressure and puts more strain on the kidneys.
Cold weather weakens the immune system, which increases the risk of urinary tract infections (which can lead to kidney inflammation) and cold weather also causes blood vessels to contract, which increases blood pressure and puts more strain on the kidneys.
Prevention and care of the kidneys
Healthy kidney function depends heavily on a balanced lifestyle, which includes proper nutrition, sufficient fluid intake and regular check-ups.
The right diet for healthy kidneys
The right diet can make a significant contribution to keeping the kidneys healthy and reducing the risk of kidney disease. A kidney-friendly diet includes:
- Low salt diet: Reduce your sodium intake to lower blood pressure and avoid stressing the kidneys. Choose fresh, unprocessed foods instead of convenience foods.
- Potassium-rich foods: Fruits and vegetables such as bananas, oranges and potatoes support electrolyte balance and kidney function.
- Avoid oxalates: Foods such as spinach and rhubarb contain oxalates, which can increase the risk of kidney stones.
Drink enough water
Adequate fluid intake is crucial to support the kidneys and rid the body of waste products.
Drink around 1.5 to 2 litres of water a day to help the kidneys with their filtering work.
Especially in hot weather or during physical exertion, you should make sure to increase your fluid intake to prevent dehydration and the formation of kidney stones.
Drink around 1.5 to 2 litres of water a day to help the kidneys with their filtering work.
Especially in hot weather or during physical exertion, you should make sure to increase your fluid intake to prevent dehydration and the formation of kidney stones.
Preventive medical check-ups
Regular check-ups are crucial for recognising potential kidney disease at an early stage. This is particularly easy with early detection from home:
Streamcheck makes it easy to monitor kidney function by analysing urine for biochemical markers. Early deviations in these values can indicate kidney disease and signal the need for a visit to the doctor.
Streamcheck also provides comprehensive analyses in a user-friendly app that allows you to monitor your health data and provide the doctor with reports.
Streamcheck makes it easy to monitor kidney function by analysing urine for biochemical markers. Early deviations in these values can indicate kidney disease and signal the need for a visit to the doctor.
Streamcheck also provides comprehensive analyses in a user-friendly app that allows you to monitor your health data and provide the doctor with reports.
Avoidance of risk factors
In order to optimally protect the kidneys, certain risk factors should be avoided:
- Smoking: Smoking damages the blood vessels and impairs blood flow to the kidneys.
- Excessive alcohol consumption: Alcohol can impair kidney function by causing dehydration and increasing blood pressure.
- Obesity: A healthy body weight reduces pressure on the kidneys and helps prevent high blood pressure and diabetes - two of the main causes of kidney damage.
Exercise and its benefits for the kidneys
Regular physical activity not only promotes general health, but also kidney function:
- Blood pressure control: Exercise helps to lower blood pressure, which helps the kidneys to work more effectively.
- Blood flow: Activity improves blood flow and helps the kidneys filter waste products. Try to incorporate at least 30 minutes of moderate exercise a day into your daily routine.
The most important information about the kidneys at a glance
Kidney health is essential for general well-being. Here are the most frequently asked questions and answers about kidney health and care.
How often should you have your kidney function checked?
Kidney function should be checked at least once a year, especially in people over 40 or with risk factors such as high blood pressure, diabetes or a family history. For people without these risk factors, it is recommended that kidney values are checked every two to three years. Check-ups usually include blood and urine tests to determine creatinine and GFR (glomerular filtration rate) levels to ensure that the kidneys are working properly.
What are the first signs of kidney disease?
Early signs of kidney disease are often subtle and can be easily overlooked. These include
- Changes in urine (colour, frequency)
- Swelling in the legs and feet (water retention)
- Fatigue and weakness due to anaemia
- Pain in the lower back or sides
How much does a kidney cost?
A kidney has no price in medical and legal contexts, as the trade in organs is illegal. In some countries, however, kidney transplants are carried out at a cost that depends on various factors such as country, insurance and medical conditions. In Germany, health insurance usually covers the cost of a transplant for patients in need.
Which foods are good for the kidneys?
A kidney-friendly diet includes
- Fruits and vegetables: Especially those that are high in potassium and antioxidants (such as berries, apples, and leafy greens).
- Water: Drinking plenty of water helps to support kidney function.
- Low salt foods: Less sodium reduces pressure on the kidneys.