I used to eat lead. It never did me any harm. The only incidents I've found for non-occupational lead poisoning (ie. Outside a lead smelter) involve eating small amounts of lead daily for several years.

Yes it's a cumulative poison, but small amounts of lead are even less dangerous than mercury.

Lead oxide has a sweet taste. So it makes sense to use it as an artificial sweetener. There was a time in the past when lead oxide was used as a calorie-free natural sweetener. But ...