Blog

A urine pH of 8 can quickly set off alarm bells in practice.
Especially in patients on a urine-acidifying diet, whether to treat or prevent struvite or recurrent urinary tract problems, the thought soon arises: do we need to acidify further?

But a single, isolated urine pH measurement is by no means always reliable enough to draw immediate conclusions from.

Urine pH fluctuates throughout the day. The value is influenced by, among other things, the timing of the measurement, the freshness of the sample, the presence of infection and — not least — the timing and size of the last meal.

The so-called “𝗔𝗟𝗞𝗔𝗟𝗜𝗡𝗘 𝗧𝗜𝗗𝗘” also plays a role here: after a meal, gastric acid is produced, temporarily releasing more bicarbonate into the bloodstream. This can be excreted via the kidneys, causing urine pH to rise temporarily.

A pH of 8 a few hours after a large meal therefore does not automatically mean that the animal has persistently over-alkaline urine — it is nothing more than a physiological response to food intake.

𝗦𝗘𝗘𝗜𝗡𝗚 𝗔 𝗛𝗜𝗚𝗛 𝗽𝗛? 𝗧𝗛𝗘𝗡 𝗙𝗜𝗥𝗦𝗧 𝗔𝗦𝗞 𝗬𝗢𝗨𝗥𝗦𝗘𝗟𝗙:
✔ how fresh is the sample?
✔ when was the urine collected?
✔ when did the animal last eat?
✔ how large was that meal?
✔ what else do we see in the urine: specific gravity, sediment, crystals, bacteria?

Only then can you say anything meaningful about the need to adjust the diet or to acidify the urine.

A high pH is not an automatic indication for acidification.
It is a measurement that needs context.

💡 𝗗𝗜𝗗 𝗬𝗢𝗨 𝗞𝗡𝗢𝗪? 💡
FeedWise also provides, for diets with sufficient available data, an estimate of the expected influence of the food on urine pH. A handy extra piece of context when making a dietary choice.

Want to try it yourself? Discover FeedWise free of charge at https://www.feedwise.nl/en/free-trial.