In the last video I mentioned how carbs can either be simple, like sugar, or complex, like starchy potatoes and because of this get released into our blood quickly or slowly. This is reflected in what is called the glycaemic index or GI. Basically, the GI is a number that represents how quickly that carbohydrate is released into the blood, pure sugar is 100, and the lower the number the slower it gets released.
So sweet potato has a GI of 44 which means, whilst it will eventually be digested into more simple carbs closer to sugar, that will take time and that energy is slowly released into the blood. That means the body can use it as it goes and it matches our energy demands and so it is less likely to get stored as fat.
However, if we have a high GI food like a baked white potato is 98, which means it basically dumps a massive load of energy into your blood at once and there is no way your body is going to need all of that in a short period so it stores it as fat.
You can search for different foods at the link below. At first, you may need to pick a few foods you commonly eat and read a few tables. After a while you will see the common patterns and will not need to research it anymore. Remember low GI foods are preferable but just because a food has a low GI, doesn’t mean it is healthy, it simply represents the speed of the energy load on your body. It does not tell you anything else about that food.