I had a bowl of Honey Nut Cheerios recently. It’d been awhile. Regular Cheerios are more my thing. But sometimes I finish my box faster than my kids do and find myself straying to their side of the cupboard.

Honey Nut is America’s best-selling breakfast cereal, and by a comfortable margin. Roughly 151 million boxes and other containers of various sizes were sold over the past year, well ahead of the second best-selling breakfast cereal, Frosted Flakes, according to IRI, a Chicago based market research firm.

I had no idea. The only thing I could think about when I ate it again for the first time in years was how incredibly sweet it is. I looked at the back of the box and could see why. Three of the top six ingredients are sweeteners: sugar, brown sugar and honey.

Previously, I assumed Honey Nut Cheerios was a slightly sweeter Cheerios, but you learn things when you finally get around to reading the back of the box. It actually has about nine times as much sugar as plain Cheerios, per serving. An Environmental Working Group analysis of a number of popular cereals — a report that linked sugary cereals to the “nation’s childhood obesity epidemic” — put Honey Nut Cheerios’s sugar content second only to Fruity Pebbles. The same group found that one cup of the cereal had more sugar than three Chips Ahoy! cookies.