What about the food industry actually producing food that does not contain excessive levels of sugar, salt, artificial colours and flavours, etc. etc.? It wouldn't go down too well with them because they know full well that some of these ingredients are addictive and therefore guarantee a regular customer base.
I do think there are too many health scares such as don't/do eat butter, don't/do drink in moderation, don't/do drink fruit juice, etc. etc. - I expect a lot of us have grown tired of the endless research results which are then contradicted a little while afterwards by another piece of research. But when it comes to heavily processed convenience "main" meals and breakfast cereals, I think there needs to be firm legislation.
Snacks like crisps and biscuits are not that good for anyone but my view is they are OK if eaten in moderation. To some extent it's up to individuals to ration these for themselves and for their families because it's fairly well known that snacks are not "healthy" foods.