Advertising probably not but the simple availability of ever sweeter cheap products and with time their integration in people's diet is a strong candidate. Espe

Advertising probably not but the simple availability of ever sweeter cheap products and with time their integration in people's diet is a strong candidate. Especially since sugar is way less good than say fat at provoking the feeling of satiation (I can think only of evolutionary explanations for that, available sweet food in the wild, think fruits, are not very nutritive, especially ones not selected by humans over time)