The worst offenders rank high on the glycaemic index (GI) – a rating system for foods containing carbohydrates.
It shows how quickly each food affects your blood sugar (glucose) level when that food is eaten on its own.
Foods with a high GI include:
- Sugar and sugary foods
- Sugary soft drinks
- White bread
- Potatoes
- White rice.
Low or medium GI foods are broken down more slowly and cause a gradual rise in blood sugar levels over time.