They tell us that fruit and vegs are good for us, and it is true. But what happens if you've got an intolerance to fructose?

The typical symptoms of intolerance to the particular kind of sugar contained in fruit are a bloated stomach, abnormal presence of gas in the digestive tract, bad breath, tiredness.

Fructose intolerance seems to occur as our bodies aren't especially well-designed to process large quantities of this type of sugar. The main sugar our body uses for energy is glucose, so we have dedicated proteins - "transporters" - to help effectively absorb it into our system. Fructose doesn't have these transporters, though, so has to hitch a ride with the glucose transporters.

However, this isn't an effective way to digest it, and so some fructose makes its way into the large intestine undigested.

Fructose malabsorption can go hand in hand with digestive disorders including IBS and Crohn's disease, a more serious condition that is a form of inflammatory bowel disease.