Of course, ‘sugar is evil’ and, by now, a great deal of scientific research has proved it to be so when imbibed in too large quantities. But sugar, whether sucrose, fructose or glucose is not unique. Ethyl alcohol is another.
Both are small, easily absorbed molecules, and have highly pleasant effects in insect and animal brains. Both are produced in nature but only in very small, occasional quantities, enough to attract either insects or fruit-eating animals which then voluntarily serve as either necessary agents (e.g. bees) between male and female plants or as distributors (any mammals) of fertilized seeds.
When sugar and ethyl alcohol can be made artificially in immense quantities, far beyond anything we can cope with safely per capita then governments will always have problems in trying to restrict both of them — so much so, in my opinion, that they will never succeed, whatever strategies they try.
The only answer to excessive consumption of either is education — that is, of people intelligent enough to take notice of scientific research on the one hand, and subsequently socialize in ways that don’t also involve excessive imbibing on the other. In other words, obesity and alcoholism — and all their serious attendant illnesses — will always be, on average, a graded social phenomenon.