It's interesting how public perception changes. The ad does have some truth - sugar is a vital nutrient.
It reminds me of an old TV ad I saw where the guy was flogging a kids' toy - "it's not made of cardboard, no. It's made of tough, long-lasting plastic."
After a long wait, I've gone ahead and changed it to 1966. Not a hundred percent sure of the year, but it's definitely no earlier than that due to the photo on the front. 1966 seems very likely.