Unfortunately, traditional gummy bears are mostly made of sugar and food coloring, so they're not even nearly ketogenic. Luckily, sugar-free gummy bears exist and they're absolutely delicious. While the bears might look innocent, they were made with a sugar substitute called lycasine, which contains the sugar alcohol maltitol. If you want to sweeten foods or drinks without refined sugar, you can consider using non-nutritive sweeteners such as stevia and erythritol.
The Academy of Nutrition and Dietetics states that consuming more than 30 grams of sugar alcohols such as lacticol, isomalt or xylitol can have similar effects. Recently, several people have come across the horror stories that have been shared in the Amazon review section about sugar-free Haribo gummy bears and they can't stop laughing. However, avoiding the effects of sugar-free gummy bears may not be that difficult, as the culprits reviewed by Amazon are no longer available. Maltitol is a substitute for sugar and sugar alcohol that is commonly consumed by people looking to lose weight or control diabetes.