We use various natural sweeteners including sugar from sugarcane, and corn (not high fructose corn syrup) to make our gummies. We chose not to use artificial sweeteners because they have been linked to bad health issues, and we wanted to stick with only natural ingredients.
We believe the health benefits that go along with enriching your diet far outweighs the slight disadvantage of delivering them with sugar. Importantly, the amount of sugar in a serving of Yumi gummies (around 2g) is roughly equivalent to eating about 5-10 raisins or drinking an eighth of a cup of apple juice.
The real benefits of Yumi gummies is that people actually enjoy taking them - so people are consistent with using them. If supplements do not get eaten because the experience is unpleasant - they are not very effective supplements!