Ask Dr Miriam

I have kidney problems. Are there any foods I ought to avoid?

Bananas are a good source of energy but you shouldn’t eat them in large quantities if you have, or have had, kidney problems as they contain large amounts of potassium.

Your kidneys regulate the amount of potassium in your body and if they function normally they can get rid of any excess.

But kidneys that don’t function normally can allow potassium to build up, potentially triggering “hyperkalemia” which causes nausea and leads to muscle weakness, tiredness, a slow pulse and an irregular heartbeat. If anything, with kidney disease, you should have a lower potassium intake. If you’ve had kidney stones, another tip is to avoid beetroot as it contains oxalates, and they prevent calcium being absorbed by combining into insoluble solid material.

Most people’s bodies can break down and eliminate these substances via the kidney. But in some people oxalates can accumulate leading to kidney stones. People with kidney stones should be vigilant about drinking enough water too.