Bezoya isn't the answer: what matters is drinking 2.5 litres a day

Bezoya isn't the answer: what matters is drinking 2.5 litres a day

Does choosing a bottled water brand actually help when the urologist has just removed a kidney stone? The short answer is barely at all. What really moves the needle is volume: urology guidelines point to urinating between 2 and 2.5 litres a day, which in practice means drinking between 2.5 and 3 litres spread throughout the day, and more if you sweat or the heat is on. Clear, almost transparent urine is the sign you're on the right track.

The experience comes from someone who has just been through it: hospitalised for renal colic, with medical advice to drink nearly two litres a day and the doubt of whether Bezoya is really the best brand. The conversation that trinc is a small treatise on kidney education with more nuances than it seems.

Is Bezoya better than tap water?

Bezoya is very low in minerals, with little sodium and little calcium, which is why it's considered balanced. So far, correct. But studies comparing hard and soft waters find little or no difference in the risk of forming stones. Tap water is perfectly fine, and in soft-water cities like Madrid, all the more so. Drinking three litres of tap water protects more than a litre and a half of the best bottled water.

The nuance about salt also matters, though for another reason: blood pressure, not the kidneys. And calcium deserves its own section, because this is where popular advice has fallen behind.

The mistake of cutting out dairy to avoid calcium stones

Most so-called "calcium" stones are made of calcium oxalate. Dietary calcium binds to oxalate in the intestine and is excreted in the stool; if you cut out dairy, more free oxalate is left, gets absorbed and ends up in the urine, promoting exactly what you wanted to avoid. A classic trial published in the New England Journal of Medicine in 2002, with men with calcium oxalate stones, found that a diet with normal calcium, little salt and little animal protein reduced recurrences by nearly 50 % compared with a low-calcium diet. Current advice goes that way: normal calcium, not restricted.

Some argue that for uric acid stones a diet change is enough; for calcium stones, the evidence points to the boring answer: plenty of water, less salt and analysing the stone if you have it.

Reverse osmosis, distillation and the turpentine hoax

In the home chapter comes the technological temptation: reverse osmosis systems that leave the water almost at zero residue, below 100 euros in some models. Don't confuse them with distillation, and remember that mineral-free water isn't ideal for the body's baseline functioning: either remineralise it or mix it. And there's no shortage of the usual hoax: adding turpentine extract to "dissolve" stones. It's turpentine, a toxic solvent that damages precisely the kidney. In case of poisoning, the Spanish Poison Information Service (Servicio de Información Toxicológica) phone number is 91 562 04 20.

In the end, the brand hardly matters. What never fails is litre by litre, without hurry and without bottled miracles.