Dear Dr Michelle,

In the first of a new monthly column, Reality Check’s favourite GP, who just happens to have diabetes, Dr Michelle ponders some of the stuff they didn't cover in med school.

To start her off, we posed a seemingly simple question:

A poll on the Reality Check website recently showed that our insulin doses vary from people down on single figures up to quite a few on more than 80 units a day, and lots of us in between.

Why do our insulin needs vary so much?

Hi there!

This is a great question to think about. But the answer might sound familiar ….. we’re all different! Isn’t that the answer to every diabetes question?

Anyway, let’s think about it a bit more …

It’s like how some people need 10 beers to get drunk and others need only one - each of us metabolise food and drink differently, have different-sized bodies and do different amounts of exercise. All these things will affect how much insulin we need (and how quickly we get drunk!).

There are other reasons too. Some people who have been diagnosed quite recently might be making a little bit of their own insulin still so will need to inject less – this is sometimes called the honeymoon period.

Some people have bigger bodies – that means you have more cells that need more keys to open the doors in their walls to let the insulin in.

Some people eat more, so will need more insulin to balance that out.

Some people have insulin resistance - where the insulin locks in the doors are rusty and they need more keys (inslulin) to force the doors open to let the glucose, from food, into the cells.

Some people do more exercise, so the glucose is forced into the cells by this rather than needing the insulin to open the doors.

There are also some other medical conditions on top of diabetes that can affect insulin doses. Someone who has a condition like Polycystic Ovarian Syndrome (PCOS) might also have a lot of insulin resistance, very rusty doors needing lots more keys (insulin) to let the glucose into the cells.

So, as always with diabetes, there’s no such thing as normal!

All the best,

Michelle

* Click here to see the poll mentioned.