There are two main issues with sugar. Firstly, sugary calorie-dense foods, such as chocolate bars or fizzy drinks, can easily be overconsumed without realising, leading to weight gain and raising the risk of diabetes and heart disease. Secondly, bacteria in our mouths ferment sugar to produce acid which causes irreversible tooth decay.
Opponents of sugar taxes and fizzy drinks makers call such measures regressive because they hit the wallets of poor consumers disproportionately. Also, they argue that these would mark the return to the nanny state and runs counter to the principle of personal choice.