The Importance of Water for Healthy Kidney Function

The kidneys are unsung heroes in the human body. These bean-shaped organs are tasked with vital functions such as filtering waste, managing electrolyte levels, and regulating blood pressure. While most of us recognise the need to stay hydrated, the specific benefits of water intake to maintain a healthy kidney function often go overlooked.  

Some years ago, Kidney Health Australia (KHA) made a clear statement with ‘Drink Water Instead.’ This highlighted the critical role water plays in both maintaining and improving kidney health. Research, including a study by Popkin, D’Anci, and Rosenberg, shows that our kidneys can efficiently remove waste products and toxins from our bloodstream when we are properly hydrated.  

Hydration and kidney health is no joke. Without enough water, our kidneys struggle and their functionality declines.  

That’s why…in this article, we’ll take you through how your kidneys work and explore how simple changes to your water intake can significantly enhance kidney health. Let’s dive in and learn how to improve kidney function naturallyy!

What Is The Function Of The Kidneys?

Think of your kidneys as a very efficient waste disposal unit. Their primary role is to filter out and collect waste materials—such as unwanted chemicals, excess fluid, and unneeded nutrients—and combine them with water which is then excreted from the body as urine.

Here’s a simple diagram of how kidneys filter blood:

However, aside from being our reliable filtering system, kidneys also perform other crucial roles in our body such as: 

• Fluid Balance: They regulate the body’s fluid balance by adjusting the volume of water excreted in urine, ensuring that hydration levels within the body are stable. 
• Electrolyte Balance: Kidneys help maintain a stable balance of electrolytes (such as sodium, potassium, and phosphate) vital for many bodily functions, including nerve transmission, muscle contraction, and heart function. 
• Blood Pressure Regulation: The kidneys help control blood pressure by regulating blood volume (through fluid balance) and releasing the enzyme renin, which helps manage arterial constriction. 
• Red Blood Cell Regulation: Kidneys produce the hormone “erythropoietin,” which stimulates the bone marrow to make red blood cells.  
• Acid-Base Balance: They help maintain the pH balance of the blood by filtering out and excreting acids or bases into the urine. 
• Maintaining Bone Health: Kidneys convert vitamin D into its active form, calcitriol. Vitamin D is obtained from the diet or produced in the skin in response to sunlight, but it’s inactive until modified by the kidneys. Calcitriol helps regulate calcium absorption in the intestines and calcium deposition in the bones, ensuring that calcium and phosphate levels in the blood are adequate to promote healthy bone formation and repair. 

With all of these critical roles that the kidneys play, it is crucial to maintain good kidney health.  

How? Well, a good first step is hydration. Since our kidneys are primarily responsible for filtering the blood and removing toxins and waste materials through urine, water becomes integral in the process. 

What Are Kidney Stones?

Kidney stones are hard mineral and salt deposits that form inside the kidneys. They are made of calcified minerals and salts, mainly calcium oxalate and uric acid (which is a byproduct of protein metabolism).  

Here’s what kidney stones look like and how they obstruct the passage of urine in our bodies: 

Kidney stones may be asymptomatic if they are present in the kidneys and do not obstruct urine flow. However, when they move into the ureters, there is a risk of severe pain, infection, and even kidney damage. Kidney stones smaller than 4mm may be able to pass by themselves, with the aid of pain medication and lots of water, but larger calcifications may need medical intervention. 

Signs and symptoms 

How do you know if you have kidney stones? Well, some of the most common symptoms to look out for are: 

• Severe Pain: The most notable symptom of kidney stones is intense pain, which can start suddenly and may come and go. The pain is usually felt in the side and back, just below the ribs, and can radiate to the lower abdomen and groin. 
• Painful Urination: As the stone moves through the urinary tract, it can cause pain during urination. This is often a sharp, burning sensation. 
• Pink, Red, or Brown Urine: Blood in the urine, known as hematuria, can occur with kidney stones, leading to a pink, red, or brown urine discolouration. 
• Cloudy or Foul-Smelling Urine: The presence of a stone in the urinary system can cause urine to appear cloudy or smell foul. 
• Frequent Urination: Kidney stones can cause an increased urge to urinate, often with only small amounts of urine passed. 
• Nausea and Vomiting: The intense pain from kidney stones can lead to nausea and vomiting, as the body reacts to the discomfort and the effect of the stones on other organs. 
• Fever and Chills: If a kidney stone leads to infection, one might experience fever and chills, which are signs of a potentially serious complication requiring immediate medical attention. 

Causes 

Several factors can contribute to the formation of kidney stones, including: 

• Insufficient Water Intake: Dehydration or low fluid intake can lead to concentrated urine, increasing the risk of stone formation as less fluid is available to dissolve urinary minerals and salts. 
• Diet: Eating a diet high in protein, sodium (salt), and sugar can increase the risk of some types of kidney stones. High sodium intake can increase calcium in the urine, leading to calcium stones. High protein intake boosts uric acid and reduces citrate, a chemical in urine that helps prevent stones from forming. 
• Obesity: Higher body weights are associated with an increased risk of kidney stones, possibly due to changes in the diet and the strain on the kidneys. 
• Digestive Diseases and Surgery: Gastric bypass surgery, inflammatory bowel disease, or chronic diarrhea can cause changes in the digestive process that affect your absorption of calcium and water, increasing the levels of stone-forming substances in the urine. 
• Other Medical Conditions: Hyperparathyroidism (overactive parathyroid glands), renal tubular acidosis, cystinuria, hyperoxaluria, and urinary tract infections can also lead to stone formation. 
• Supplements and Medications: Excessive use of vitamin C (ascorbic acid) supplements, laxatives (when used excessively), calcium-based antacids, and certain medications used to treat migraines or depression can increase the risk of stone formation. 
• Family History: If kidney stones run in the family, you’re also more likely to develop stones. 
• Personal History: If you’ve had one or more kidney stones before, you’re at increased risk of developing another. 

Treatment 

The treatment for kidney stones varies depending on the size of the stone, its location, the type of stone, and the severity of symptoms. Here are the main approaches to treating kidney stones: 

• Hydration: For small stones, increasing water intake to help flush out the urinary system may be sufficient. The recommendation is to drink enough water to produce clear or nearly clear urine. 
• Pain Relief: Over-the-counter pain relievers such as ibuprofen, acetaminophen, or naproxen can help manage the pain associated with kidney stones. 
• Medications: Your doctor might prescribe medications to help you pass a kidney stone. These drugs, known as alpha-blockers, relax the muscles in your ureter, helping you pass the kidney stone more quickly and with less pain. 
• Lithotripsy: For stones that don’t pass on their own or cause severe symptoms, a procedure called shock wave lithotripsy might be used. This treatment uses sound waves to break up stones into smaller pieces enabling them to pass more easily.  
• Laser Fragmentation: Recent developments have been made in the treatment of kidney stones. A fiberoptic scope is passed up the ureter to the kidney, where the stone can be visualised. A laser fibre is then sent to fragment the stone and make it easier for the kidney to flush it out. 

While patients previously needed to undergo surgery and spend several days recovering in hospital, they are now able to undergo this simple pulverisation procedure in one day. 

Prevention 

While treatment options are now available, knowing prevention is always better than intervention!  

So how, you may ask? The short answer lies in improving your kidney health. Changing your lifestyle choices can play an important role in such endeavours. Continuously implementing ways to enhance kidney health can prevent the development of kidney stones in the first place, which could save you a lot of pain down the line.  

How To Improve Kidney Health 

Understanding how to improve kidney function is key to living a long life.  

Since keeping kidneys healthy is crucial for maintaining your overall health, there must be some lifestyle habits and general tips on how to improve kidney function, right?  

Definitely. There are 3 key areas to address – exercise and lifestyle, diet as well as hydration! 

Exercise and Lifestyle 

To kick off our journey into healthier kidneys, let’s dive into the vital role of exercise and lifestyle choices: 

• Engage in regular physical activity: Regular exercise helps regulate blood pressure, which is crucial for preventing kidney damage that can arise from hypertension. 
• Maintain a healthy weight: Obesity is linked to diseases such as diabetes and hypertension, both of which are major risk factors for chronic kidney disease. 
• Stop smoking: Smoking impairs blood flow to the kidneys, potentially worsening kidney function and accelerating the decline in kidney health. 
• Limit alcohol consumption: Excessive alcohol can cause changes in the function of the kidneys and make them less able to filter blood. 
• Keep an eye on cholesterol levels: High cholesterol can lead to atherosclerosis, which can decrease blood flow to the kidneys and impair their function. 
• Undergo regular health screenings: Regular check-ups can help detect early signs of kidney damage so that intervention can begin as soon as possible. 
• Be aware of your genetic health risks: Some kidney diseases are hereditary. Knowing your family medical history can help you take early precautions. 

Diet 

Exploring how diet impacts your kidney health is crucial, particularly in preventing kidney stones. Here’s a closer look at what to eat and what to avoid to keep your kidneys functioning optimally: 

Foods to ensure healthy kidneys: 

• Citric acid (from oranges, lemons, and grapefruits) prevents calcium from binding to other substances, reducing the formation of crystals. 
• High calcium foods, such as dairy products, with foods containing oxalates (chocolate, sweet potato, peanuts, seeds, beets, okra, spinach, tea, soy products). This ensures that the calcium and oxalates bind in the intestinal tract instead of the kidneys. 

Foods to avoid: 

• Limit foods containing oxalates (chocolate, sweet potato, peanuts and seeds, beets, okra, spinach, tea, and soy products). 
• Avoid foods high in salt. Salt helps move calcium from the blood to the urine, so excess salt results in more calcium in the kidneys. 
• A diet high in red meats, organ meats, and shellfish. These foods contain a naturally occurring chemical called purine, which leads to a higher production of uric acid, and uric acid stones. 
• Limit sugar intake in order not to develop or exacerbate kidney stones 
• Alcohol reduces the removal of uric acid from your body, so keep it to a minimum 

Hydration and Kidney Health 

Let’s say it one more time for the folks in the back: Staying hydrated isn’t just good advice—it’s a lifeline for your kidneys. Not enough water? That’s a one-way ticket to Kidney Stone City.  

More water means more urine, which helps keep those pesky minerals from cozying up together and forming stones.  

When the body lacks enough water, the kidneys struggle to perform their basic functions. Dehydration produces less urine, meaning toxins and waste materials are not flushed out as they should be. AND, when you don’t drink enough water, there is less fluid in your urine, meaning the toxins and waste materials can’t dissolve properly and are more likely to clump together, solidify, and turn into what we now call “kidney stones.” 

Think of drinking water as your kidney’s best friend—it helps flush out toxins and keeps everything running smoothly. 

So, fill up that water bottle and drink up to keep those stones at bay and your kidneys in tip-top shape! 

How Much Water Should We Drink To Keep Kidneys Healthy?

Now that we’ve highlighted the critical role of hydration for your kidneys, you might wonder, “how much water to drink for healthy kidneys”?  

Well, the amount of water you should drink to keep your kidneys healthy can vary based on several factors such as: 

• Activity Level: If you are very active and sweat a lot, you must drink extra water to compensate for the fluid loss.  

Water Intake Advice: The American Council on Exercise suggests drinking about a cup of water every 10 to 20 minutes during exercise to stay hydrated However, more intense or prolonged physical activity can require much more fluid intake. 

• Climate: People living in hot or dry climates may need more water to stay hydrated. 

Water Intake Advice: Increase intake to 8-12 glasses a day. 

• Health Conditions: Certain health conditions, such as kidney stones or urinary tract infections, might require drinking more water. In these cases, it’s important to follow the guidance of a healthcare provider. 

Water Intake Advice: If someone has had a kidney stone, they should drink at least two litres per day to reduce the risk of another one. If you have previously suffered from kidney stones, drinking 2L of water daily can reduce your chance of recurrence from 50% to 15% over 5 years. People with certain health conditions—including end-stage renal failure—may need to reduce their fluid intake in accordance with their doctor’s advice. 

• Diet: If your diet includes lots of fruits and vegetables, which contain water, you might not need to drink as much fluid. On the other hand, if you eat a lot of salty or high-protein foods, you might need more water to help your kidneys remove the extra waste products. 

Water Intake Advice: A good rule of thumb for individuals is to aim for about 1.5 to 2 litres of water per day or roughly eight 8-ounce glasses. 

Maintaining proper hydration is crucial, given that the body typically loses between two and three liters of water daily through processes like urination, perspiration, and respiration. Water is the most recommended beverage for staying hydrated because, unlike sweetened drinks, it doesn’t harm dental health or contribute to Chronic Kidney Disease (CKD) when consumed excessively. 

Worried About Your Kidney Health? 

If you’re experiencing symptoms of kidney stones or have concerns about your overall kidney health, it’s important to consult a professional. At Katelaris Urology, our kidney stone specialists are ready to discuss treatment options, including kidney stone removal, and strategies for reducing your risk. Schedule a consultation today to explore treatment, management, and prevention strategies. Our experienced urologists will also guide you through the right nutritional steps to prevent future occurrences of kidney stones. 

References: 

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