Did you know? Your kidneys filter approximately 180 liters of blood plasma every day to produce urine. This continuous purification process prevents the accumulation of waste products in the body and is directly dependent on your hydration level . The water you drink influences both the volume and concentration of your urine . Furthermore, certain minerals present in water can, depending on your health, either facilitate or hinder kidney function .
This content is provided for informational purposes only. It is not a substitute for professional medical advice. For any specific medical condition or illness, consult a doctor or qualified specialist.
Hydration: a cornerstone of kidney health
Why is water essential for the kidneys?
The kidneys ensure the filtration of the urinary system . They rid your blood of waste products such as urea, creatinine and other toxins every day, while regulating blood pressure , blood pH and fluid and electrolyte balance .
Adequate hydration maintains proper blood flow, which promotes the efficient elimination of waste . Dehydration has the opposite effect . Blood volume decreases, and your body triggers hormonal mechanisms to conserve water: filtration slows down, and urine becomes more concentrated.
When dehydration becomes chronic , the risk of crystal and kidney stone formation (lithiasis) increases, particularly in predisposed individuals.
How much water should you drink each day?
A healthy adult should aim for a water intake of at least 1.6 to 2 liters per day, in addition to the water contained in food according to the recommendations of Anses.
This amount varies depending on your weight, your level of physical activity, and the ambient temperature . The goal is to maintain a sufficient urine volume , ideally around 2 liters each day.
The color of your urine is an excellent indicator. A pale yellow tint confirms good hydration , while a dark color signals that you need to drink more. Visit our hydration quiz for personalized recommendations!
What is the best water for the kidneys?
Top 3 recommended waters
1. Low mineral content waters
Mineral waters like Volvic or Mont Roucous are suitable for daily consumption. Their low mineral content (less than 500 mg/L of dry residue) means they don't require any additional expense . Tap water , often low in minerals in most regions, is also a suitable alternative . In France, tap water must meet more than 60 potability criteria set by the Public Health Code.
2. Waters rich in bicarbonates
Waters rich in bicarbonates, such as Vichy Célestins or Saint-Yorre , increase urinary pH and citrate , an inhibitor of uric acid crystallization . However, some contain high levels of sodium . They should be consumed in moderation if you suffer from hypertension.
3. Waters rich in magnesium
Brands like Hépar or Contrex provide a significant amount of magnesium . This mineral can bind to oxalate and reduce crystallization , thus preventing certain kidney stones. However, be careful if you have previously developed calcium stones, as some magnesium-rich waters contain high levels of calcium.
Which water should be avoided if you have kidney stones?
There are no universal rules: everything depends on the type of kidney stone and the mineral profile of the water. If you have calcium stones , for example, you should especially avoid hard water, such as water rich in calcium. You should consult a nephrologist or urologist to obtain a personalized recommendation , based on your urine tests, your history of kidney stones, and your lifestyle.
Is drinking too much water bad for the kidneys?
If you are healthy , your body eliminates excess water . However, overhydration (several liters in a short period of time) can cause hyponatremia .
In cases of chronic kidney failure , drinking too much can worsen the situation, as weakened kidneys struggle to manage excess fluid. For patients undergoing dialysis , fluid intake must be strictly monitored by a doctor to avoid any overload .
Is hot water beneficial?
No scientific evidence demonstrates that water temperature influences kidney filtration. The most important factor remains the total amount of water consumed . Therefore, you can drink it lukewarm, cool, or at room temperature (the latter option aids digestion).
What drinks and foods can protect your kidneys?
Beneficial drinks
In addition to water, unsweetened infusions such as chamomile, dandelion, nettle, or green tea support hydration. Certain fruit and citrus juices (grapefruit, apple, orange, lemon, etc.) appear to protect against kidney stone formation in some cases.
Drinks to limit or avoid
Limit sodas and fruit juices with added sugars . Their high fructose and phosphoric acid content can lead to kidney stones.
Energy drinks containing caffeine or taurine should also be consumed in moderation as they increase the kidney load.
Good eating habits
- Opt for a diet rich in fruits and vegetables , which contribute to varied and optimal hydration.
- Reduce your consumption of processed foods , deli meats and canned goods that contain too much salt.
- Limit animal protein to about 0.8 grams per kilogram of body weight per day to avoid urea overload.
- Maintain an adequate intake of dietary calcium . Contrary to popular belief, this does not increase the risk of kidney stones, unlike supplements.
It's important to distinguish between dietary calcium and calcium supplements . Calcium from your diet (dairy products, green vegetables, certain mineral waters) does not promote kidney stones and can even limit crystal formation. Supplements, on the other hand, can increase the risk of kidney stones and should only be taken under medical supervision.
What is the best vitamin for the kidneys?
Vitamin D is often cited for its role in calcium and phosphorus metabolism. Studies also show that vitamin B6 may reduce oxalate production in some cases.
Never take supplements without consulting your doctor . Your needs vary depending on your condition, and any overdose can worsen your situation.
Preventing kidney stones and kidney disease: what you need to know
How to avoid kidney stones?
A healthy lifestyle is the best form of prevention. To achieve this:
- Stay well hydrated every day to dilute any substances that could form crystals.
- Engage in regular physical activity .
- Do not exceed the recommended daily dose of salt (5 g).
- Moderate your intake of animal protein. and eat fruits and vegetables.
How to stop the progression of kidney failure?
Consume citrus fruits rich in citrate and reduce foods containing a lot of oxalates such as spinach, rhubarb, soy products, chocolate, beets or nuts.
Adjust your protein intake according to the recommendations and avoid non-steroidal anti-inflammatory drugs (NSAIDs). You should also regularly monitor your blood pressure , creatinine, potassium, and sodium levels.
Do not exceed a dietary calcium intake of approximately 1000 mg per day.
What foods should be avoided in case of kidney failure?
Your diet should be adapted to your stage of the disease and monitored by a nephrologist or a specialized dietitian. You should limit all foods rich in potassium (bananas, avocados, dried fruit, chocolate) and phosphorus (dairy products, offal, sardines, legumes).
FAQ – Answers to frequently asked questions
What is the best water for kidney function?
According to UFC-Que Choisir, Mont Roucous is considered one of the best waters thanks to its low mineral content. When choosing between two brands, always select the one with the lowest dry residue: the lower the residue, the less the water puts on your kidneys.
What is the best drink to cleanse the kidneys?
As we explained previously, low-mineral water is the preferred option. It doesn't cleanse in the strict sense, but it contributes to the body's natural drainage process of accumulated waste.
Does drinking lots of water really cleanse the kidneys?
Sufficient intake facilitates waste elimination. However, excess intake does not optimize kidney function and can be dangerous. Divide your intake into small sips throughout the day and adhere to the recommended daily amount based on your individual needs.
Conclusion
Choose low-mineral waters : they facilitate kidney filtration without overloading the body. Whether you are in good health or undergoing treatment, maintaining regular hydration tailored to your individual needs remains a priority. If you have a kidney condition or a history of kidney disease , your healthcare provider should be able to guide you toward specific choices.
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