Whilst eating Keto is not a magic bullet and will not suit everyone, the reason why it does seem miraculous to many people is based in science. If you want to understand how Keto helps people lose weight and get healthy, read on…
When humans eat a standard Western diet their bodies depend on glucose for energy. This is why many people get tired in the afternoon when their blood sugar drops. Their body is telling them to eat more carbohydrates or sugar (a form of carbohydrate) in order to give them more energy, because the last lot is running out. The problem is that when we eat mostly carbohydrates, especially refined ones, and not enough protein and fat, our blood sugar goes on a roller coaster that’s way too steep.
The main player in this roller coaster ride is the hormone insulin, also known as the fat storage hormone. What happens when we eat sugar or other carbohydrates is that they turn into glucose in our blood, which we use for fuel. Insulin responds to glucose, signaling to the body to put the glucose into the cells where it can be used for energy. However, when we have too much glucose we have to store some for later as glycogen (like charging our spare battery) and the rest goes to the liver to be turned into fat.
When we eat excessive sugars and carbohydrates our body must produce a lot of insulin to make sure our blood sugar does not stay too high (which can be very dangerous). Unfortunately if the body produces too much insulin in its attempt to avoid high blood sugar, the result is that our blood sugar levels start getting too low because the excess of insulin keeps shuttling glucose into the cells, unaware its not needed anymore. This overcorrection is sort of like if you swerve in the car to avoid an obstacle but then turn too far the other way.
Then after a short time the body sends out signals to tell us to eat more because low blood sugar is also dangerous (hence the afternoon munchies). When this cycle continues over time, like a big steep roller coaster of blood sugar levels, the body can eventually become resistant to insulin (kind of like if someone yells at you a lot and you learn to block them out). So at this point the body has theoretically got enough insulin, but the cells aren’t responding properly, so you eat some more and the cycle continues. This is the precursor to diabetes.
Carbohydrates are actually the only non-essential macronutrient (the others being fat and protein, which are required for survival). When you eat a Ketogenic diet, you do not have enough glucose in your body for all your energy needs. So the body uses fat as its main fuel source. Or more specifically, the liver turns fat (either from food or your body) into ketones, which can be used by the body for energy instead of glucose.
When you eat a diet high in fat, moderate in protein and low in carbohydrates (i.e. Keto) the body goes into ketosis, and burns dietary, and stored body fat for energy, as opposed to storing extra fat when insulin gets out of control. The Ketogenic diet has also been shown to reduce ghrelin levels (the body’s main hunger hormone) and reduce cravings, because now the body can have access to constant energy (from fat) without needing you to eat as regularly or consume as many carbohydrates as when you were on the insulin roller coaster.