Kidney stones are painful, but for many people living in hot parts of Spain they are also preventable. Understanding how heat, dehydration and diet affect your kidneys makes it much easier to reduce your risk and look after your long‑term health.
Why kidney stones are more common in hot climates
When the weather is hot, you naturally lose more fluid through sweating. If you do not drink enough to replace that loss, your urine becomes more concentrated, giving minerals like calcium, oxalate and uric acid a better chance to crystallise and form stones.
This is why kidney stones are more common in hotter regions and during summer months, and why outdoor workers, golfers, hikers and people who exercise in the heat are at particular risk. Long periods of mild dehydration, day after day, can gradually set the stage for stones even if you feel “fine” most of the time.
Other factors that raise your kidney stone risk
Heat and dehydration are only part of the picture. Other important risk factors include a family history of stones, previous stones, obesity, type 2 diabetes, high blood pressure and certain medications or medical conditions that affect mineral balance in the body.
A diet high in sodium (salt), large amounts of animal protein, very sugary drinks and low intake of fruits and vegetables also makes stones more likely. Many of these factors overlap with those that affect heart health and blood pressure, which is why a kidney‑friendly diet often looks very similar to a heart‑healthy one such as the DASH diet for lower blood pressure or a Mediterranean‑style pattern.
How much should you drink in Spain’s climate?
For kidney stone prevention, the usual aim is to drink enough to produce pale, almost clear urine throughout the day. In practical terms, many adults need at least 2 to 2.5 litres of fluid per day in mild weather, and more during hot spells or if they are active outdoors.
Plain water should make up most of this intake. Unsweetened herbal teas and sparkling water can help you reach your target, but sugary drinks and large amounts of cola or sweet fruit juices are best kept for occasional use. If you know you struggle with dehydration, our articles on what dehydration is and signs of electrolyte imbalance are useful companions to this guide.
Using citrus and citrate to protect your kidneys
Citrus fruits such as lemons, limes and oranges naturally contain citrate, a compound that helps prevent stones by binding calcium in the urine and reducing crystal formation. This does not mean lemon water can “dissolve” existing stones, but it can be one useful part of a prevention plan.
Simple options include adding freshly squeezed lemon to your water, using citrus in salads and cooking, and making use of Spain’s winter orange season with whole fruit or small amounts of fresh juice. If you are interested in the wider benefits of citrus, see our articles on how oranges can improve your health and the health benefits of kiwifruit.
Salt, protein and kidney‑friendly eating
Too much salt in your diet increases the amount of calcium your kidneys have to handle, which can encourage stone formation. In Spain, this can come from cured meats, some cheeses, ready meals, crisps, olives, stock cubes and salty snacks. Reducing salt is also good for your blood pressure and heart, as explained in cholesterol‑lowering foods that actually work and 16 foods for a healthier heart.
Very high intakes of animal protein (large daily portions of meat and processed meats) can make urine more acidic and increase levels of substances like uric acid and calcium. A kidney‑friendly pattern usually means getting protein from a mix of sources: fish, poultry, eggs, pulses, nuts and seeds, alongside plenty of vegetables. This looks very similar to the Mediterranean‑style and DASH‑style diets you may already recognise.
What about calcium and oxalate?
It might seem logical to cut out calcium if you have had calcium‑based stones, but this is rarely recommended without medical advice. Too little calcium in your diet can actually increase stone risk by allowing more oxalate from food to be absorbed into the bloodstream and then excreted in the urine.
For most people, the goal is to obtain a normal amount of calcium from food (such as dairy products or calcium‑rich plant foods) while moderating very high intakes of oxalate‑rich items like large quantities of spinach, beetroot, nuts or dark chocolate. Your doctor or kidney specialist can give tailored advice if you have a known stone type or other conditions affecting calcium balance.
Types of kidney stones and why they matter
Not all kidney stones are the same, and the type you have can slightly change the prevention strategy. The most common are calcium‑based stones (usually calcium oxalate, sometimes calcium phosphate), which are strongly influenced by hydration, salt, calcium and oxalate intake.
Uric‑acid stones are more likely in people with high uric acid levels, gout, very high animal‑protein intake or poorly controlled type 2 diabetes. Infection‑related stones are linked to recurrent urinary tract infections and often require both antibiotics and urology input. Knowing the stone type from lab analysis, if possible, helps your doctor tailor diet and medication more precisely for you.
Kidney stones, weight, diabetes and heart health
Kidney stones, high blood pressure, type 2 diabetes and heart disease share many of the same underlying risk factors: excess weight, a very processed diet, high sugar intake, inactivity and chronic dehydration. The good news is that changes that protect your kidneys often support the rest of your body at the same time.
If you are working on weight or blood sugar, our guides on managing and understanding type 2 diabetes and are you eating too much sugar? fit neatly alongside kidney‑friendly advice. Many of the same eating patterns that help prevent stones also support healthy cholesterol and blood pressure, which we cover in more detail in the DASH‑style and heart‑health articles mentioned above.
Digestion, gut health and kidney stones
Your gut and kidneys are more connected than they might seem at first glance. Conditions that affect digestion, long‑term use of certain antacids or laxatives, and very restrictive diets can all influence how minerals and fluids are absorbed and excreted, which in turn can affect stone risk.
Building a stable, fibre‑rich diet that supports your gut microbiome makes it easier to maintain a healthy weight, better blood sugar control and more consistent hydration habits. For ideas on how to do that in everyday life, see our articles on improving digestive health and the gut microbiome and mental health.
If you’ve already had a kidney stone
Anyone who has passed one stone has a higher chance of forming another, especially if nothing changes in terms of hydration and diet. Many people will form a second stone within a few years if they do not address the underlying risk factors, which is why follow‑up after a first episode is so important.
After a stone, it is worth asking your doctor about checking blood pressure, blood sugar, weight and, in some cases, doing a 24‑hour urine test to look at calcium, oxalate, uric acid and citrate levels. Depending on the results and your stone type, medication such as potassium citrate or thiazide diuretics may be recommended alongside lifestyle changes. Following up properly gives you a much better chance of avoiding another painful episode.
Practical day‑to‑day tips for expats in Spain
In real life, protecting your kidneys in Spain’s heat comes down to a few repeatable habits. Helpful steps include:
- Start the day with a large glass of water and sip regularly rather than waiting until you feel very thirsty.
- Increase fluids on hot days, beach days and when you are active outdoors, aiming for pale urine by early afternoon.
- Limit very salty foods and heavily processed snacks, especially if you already have high blood pressure.
- Use citrus regularly in water, salads and meals to boost natural citrate intake.
- Base most meals on whole foods: vegetables, fruit, whole grains, pulses, fish and modest amounts of lean meat.
- Keep alcohol and sugary drinks as occasional extras rather than everyday staples.
These simple routines tie together hydration, digestion and heart health in a way that protects your kidneys without feeling like a complicated “kidney diet”.
When to see a doctor about kidney pain or stones
Severe, cramping pain in the side or lower back that comes in waves, often radiating to the groin, can be a sign of a kidney stone. This may be accompanied by nausea, vomiting, blood in the urine, urgent urination or a burning sensation when you pass urine.
If you have this type of pain, especially with fever, chills or difficulty passing urine, you should seek urgent medical attention. Stones can sometimes block the urinary tract and lead to infection or kidney damage if not treated. If you are unsure how to access care, our guide how to register with a doctor in Spain explains how to get started with the system.
Looking after your kidneys in Spain’s climate
Living in a sunny, warm country like Spain brings many health benefits, but it also means paying extra attention to hydration and diet. Kidney stones are common and extremely painful, yet in many cases they are preventable with the right habits.
By drinking enough, limiting excess salt and highly processed foods, using citrus to your advantage and following the same heart‑ and diabetes‑friendly patterns we recommend elsewhere on our site, you can significantly reduce your risk. Your kidneys quietly work for you every day; giving them a bit of extra care is a smart investment in your future health.
Need help choosing or using a GP with Sanitas?
If you are worried about kidney symptoms or want to review your risk factors, speaking to a general practitioner is a sensible first step. With Sanitas plans, you can book in‑person or video GP appointments easily and get referrals for any tests or specialist opinions you might need.
Read our guide to primary care and general practitioners with Sanitas to see how GP appointments, referrals and everyday family healthcare work within the Sanitas network.
