The #1 product in this category is Kellogg's Honey Smacks which contains 55.6% of sugar by weight. The 2nd product which has 51.9% sugar by weight is Post Golden Crisp followed by Kellogg's Froot Loops Marshmallow with 48.3 % sugar. The list in descending order of sugar content includes Quaker Oats Cap'n Crunch OOPS! All Berries Quaker Oats Cap'n Crunch original, Quaker Oats, Kellogg's Smorz, Kellogg's Apple Jacks and Quaker Oats Cap'n Crunch's Crunch Berries. In last place, a somewhat doubtful achievement is Kellogg's Froot Loops original at 41.4 percent sugar by weight. All sounds astonishing but it is true, the moms need to beware of their kids' safety.