Nutrition Videos

Hi! I'm Stelios Pantazis and I'm a doctor. I specialize in medical nutrition and metabolic disorders. In this video we will address a very important subject, regarding blood sugar and insulin. About 20 years ago, a group of brilliant scientists, mostly from the University of Sydney, in Australia, decided to perform a very clever experiment. To see how fast glucose contained in food is released in the blood in a set quantity. So the meals had a set amount of carbohydrates. They measured how long it took them to enter the bloodstream. They chose healthy volunteers. They gave them fruit and cooked food or raw food. Then they did blood tests. Like the glucose curve that shows if you have diabetes. They measured the rate and speed of glucose release in our blood. A very clever move. That's how the glycemic index came to be. It gives us a great overview of how fast any food raises our blood sugar. The glycemic index was a very clever and useful invention, and an eye-opener regarding some foods. We started to view them differently. Some that were thought to be harmful turned out to be better than what we thought. Mostly fruit. Many weren't sure how they affect blood sugar, since they're sweet. But they actually have a low glycemic index, which is a good thing. It means that sugar in our blood increases at a slow rate. We want that to happen. On the other hand, some foods that were being regarded favorably turned out to be not as healthy because they release carbohydrates very fast in the bloodstream, causing a harmful hormonal state in our system. The glycemic index guided us for 20 years, but we also saw its limitations. The main limitations are the following. Firstly, that study was conducted on healthy volunteers. People who have diabetes have a different reaction. Of course, that doesn't make it useless. It's useful, but mostly for people who don't have diabetes. If you have diabetes, it's a different deal altogether. Also, some foods do not increase sugar, but affect insulin. There are foods with little or no carbohydrates at all. However, they do increase insulin. So a few years ago we got an updated version of the glycemic index. It's called insulin index. Instead of checking how a food affects sugar, we take a step back and check how it affects insulin. Very important for people who are at a high risk of getting diabetes and for those who already have it, of course. But it's mostly a tool for prognosis. Because some people who are at risk of having diabetes, either because their parents had it or women who got it during pregnancy, so people who are at risk of developing diabetes in the future, should have their insulin index checked instead. I.e. to avoid foods that increase insulin fast, instead of sugar. The insulin index has not been studied as much. It's mostly based on healthy people, not people that have diabetes. But it does give us a better picture of various foods. We saw something really impressive. We saw that protein increases insulin just as fast as processed carbohydrates. I'll use some examples of food to make it clearer for you. A plate of roast chicken increases insulin just as much as a plate of pasta. Most people aren't aware of this. So it's quite common, when people want to manage their diabetes or want to avoid getting it in the future, they avoid eating carbohydrates, they eat lots of protein, they avoid fatty foods to keep their cholesterol down. So they mostly eat roast meat. Chicken and beef. But this has the opposite outcome. Instead of not increasing insulin, as they need to, it increases it just as much as if they were eating processed starch. Pasta, flour. Foods that, when it comes to diabetes, or if you are at a high risk of having it, you need to avoid them or consume very little of them. So even clean, roasted meat has the same effect. So what do we do in this case? If we want to prevent it, what do we do? Avoid both carbohydrates and protein? What's left for them to eat then? They can eat traditional Greek dishes. Legumes and vegetables cooked with oil. Food that Greeks always ate. Greens, green beans, okra, beans, lentils. Foods high in protein and carbohydrates. If cooked properly with olive oil, the oil will prevent an abrupt increase of insulin. It's a whole and healthy diet, ideal for people who are at risk of having diabetes. So you should turn to the food people ate in Greece 50-100 years ago. It's ideal for people who worry that they may develop diabetes. That's all for now. Thank you!