Another option to reduce your blood sugar levels is to simply focus on eating whole foods. Sure, you can look at the glycemic index, but what it will tell you is that most refined foods have a high GI and most whole foods have a low GI.
A whole food, if you're not familiar with the term, is basically what it sounds like. A banana. An egg. Oatmeal.
Of course, meat, whole milk cheese, butter, etc. are also whole foods, so that's not the whole story. I like Michael Pollan's rules: Eat food. Mostly plants. Especially leaves.