Sugar is added to biscuits to enhance their taste. It is the sugar that causes a sudden spike in energy. Indian Standard has not prescribed a specific limit but a higher quantity of sugar is not desirable. In particular, diabetics have to be careful about choosing biscuits that are low in sugar. You can check the amount of sugar by reading the details given on the label. Sugar was highest in Anmol (22.5 per cent) and lowest in Britannia (17 per cent).