In general, potatoes are very starchy vegetables. A baked russet potato is a high 85 on the glycemic index. Keep in mind that glucose is 100. Eating this staple root vegetable is quite nearly the same as eating processed table sugar. The carbohydrates in potatoes are quickly turned into glucose during digestion and will cause a blood sugar spike; therefore, they should be eaten very sparingly. Potatoes should also be eaten with their skin, for the skin contains the bulk of the potato’s fiber and helps to lower the glycemic index of the potato. However, neither all varieties of potatoes nor their methods of preparation are created equal. A boiled sweet potato, which is considered to be among the healthiest of potatoes, is a mid-range 46 on the glycemic index, while a baked sweet potato is a very high 94. Because sweet potatoes have beta-carotene, they can slow digestion and lower glycemic index. Next, consider red potatoes. When red potatoes are boiled, their glycemic index is 89, but their glycemic index falls to 56 when they are consumed cold. (When the structure of the starches in a vegetable is altered, the glycemic index is altered as well.) Although potatoes are a starchy vegetable, diabetics can eat them in moderation if they are prepared correctly and eaten with healthy fats, fiber, and proteins to avoid a drastic spike in glucose levels.