Is the amount of sugar some of us eat and drink, damaging to our health? In this fact sheet: What are 'free sugars'? Will sugar rot my teeth? Sugar in fruit Small amounts used to sweeten foods are fine, preferably at mealtimes, so there is less risk of damaging your teeth. However, many of us have too many high-sugar foods and drinks too often. Added sugar is not necessary for a healthy diet, and sugar-sweetened beverages have been linked to obesity, especially in children.