< Previous: How our body works I
AND THIS IS WHERE WE START.
If you remember from the previous part, ATP is the main form of energy for cell metabolism.
The glucose molecule is incredibly important to our body, as it is necessary for the production of ATP.
Normal blood glucose levels, our blood sugar, range from 70 to 110mg/dl. When these levels are exceeded, homeostasis takes over to bring them back up.
Getting to the point: When the pancreas secretes insulin, the glucose in the blood is either converted into glycogen to go to the muscles and liver, or stored as fat, and so during this process its levels drop to normal.
So, we can say that the glucose is the main source of energy for our cells and insulin helps to transport it there.
In addition to insulin, the pancreas also secretes another hormone, glucagon, which is responsible for exactly the opposite effects: it signals the process of energy production by the catabolism of amino acids, fatty acids and glycogen, thus increasing blood glucose levels.
In a nutshell, every time we eat, the energy we get from our food is used as a direct source of energy and stored as fat. After a few hours, when insulin levels have dropped and glucagon levels have risen, this process stops and begins to use stored fat as an energy source.
And because we are more concerned about fat loss, we keep the following:
- When insulin levels are high, the body stores glucose as fat to use as an energy source in the future.
- When insulin levels are low, the body uses this stored energy.
Let's make a simplified graph to make it easier to understand:
For purely formal reasons, I also provide a more realistic graph:
Now, if you object to the simplified form in which I present this information to you, I grant you. It's true, we should be focusing on glucagon levels rather than insulin levels, since we're interested in fat loss. Because glucagon actually signals the catabolism of amino acids, fatty acids and glycogen to raise glucose levels in the body when they drop. And glucagon doesn't go up as soon as insulin drops and so on. But this simplistic way of thinking is enough and enough for us not only to understand what is optimal for our goals, but also in practice since by controlling insulin levels, we can also control glucagon levels.
Let's go a little further. There are foods that raise insulin levels sharply and greatly, some more moderately and some even less. When a food increases insulin levels in the body it is called insulinogenic. How sharply and how long it takes for the pancreas to stop secreting insulin depends on the type of food and the insulin resistance that a particular person has.
What is insulin resistance? Insulin-dependent cells that do not respond properly to normal circulating levels of insulin. This results in the pancreas needing to secrete more insulin in order for the same amount of glucose to be stored in these cells as before. This phenomenon is called insulin resistance and its opposite is insulin sensitivity..
In fact, insulin resistance and consequent chronic hyperglycaemia are considered an important factor in the development of type II diabetes. Here, let me preempt you before you jump to conclusions and mention that chronic overeating of dietary fat can lead to insulin resistance according to research such as this.
So, with the excuse that carbohydrates increase insulin levels, which in turn stores glucose as fat, it's easy for a new diet fad to break out every few years on the grounds that carbohydrates are to blame for obesity, not that someone is eating mindlessly. Easy Sell.
- "Can I tell you something?"
- "What?"
- "I discovered this incredible weight loss method. And you'll eat fantastic food too. No more hunger pangs. You'll eat steaks, fried eggs, ribs, burgers, sausages. All the good stuff."
- "No way, it's a scam, right?"
- "No, all of this has the backing of science. You'll see results, or your money back. Hurry, the offer is only available in limited numbers."
You can see how attractive that is. For the most part, high-fat diets tend to make you feel full, and so there are lots of no-word-to-count-calories-that-science-says-so variations. Serious science, man.
These are the ketone diets and we'll talk about them another time. As we will see later, the reality is different. NOT HOW YOUR BODY WORKS.
Coming back to how abruptly and how long it will take for the pancreas to stop secreting insulin and the type of food, there are some tools for calculating this so that people with high blood sugar levels in the body can be helped and avoided. These tools have been touted as useful for those who want to lose weight, since it is assumed that insulin secretion in the body will be smoother, as if eating mindlessly by consulting these indicators will make any difference in slimming:
- Glycaemic Index (GI). The oldest measurement system. It is how much a carbohydrate food can potentially raise blood glucose levels compared to pure glucose (usually). Glucose has an index of 100 and foods with an index of 70 and above are considered to have a high index, those from 56 to 69 a moderate index and those from 55 and below a low index.
- Glycaemic Load (GL). A newer measurement system than the glycaemic index. The problem with the glycemic index is that it does not take into account the perceived amount of carbohydrates in the food in question. For example, watermelon has a GI of 72, while a Snickers has a GI of 51. Doesn't that sound absurd? And it is. A Snickers has 33 grams of carbohydrates and to get that many carbohydrates you need to consume more than 400 grams of watermelon! So the glycemic load takes into account the amount of carbohydrate the food provides.
In case you are interested in this, I have provided three lists that list the glycemic indexes and glycemic loads of an exhaustive list of foods.
Harvard health: Glycemic Index and Glycemic Load for 100 foods
Let's go a little further though. Do you see a problem so far?
If your answer was no, then you have been misled. Let me clarify what I am saying: These people are selling you that they are concerned about burning fat, but instead of being concerned about insulin levels, they are concerned about glucose levels and how carbohydrates affect them. Why is that?
If the person who wants to lose weight is a diabetic I understand - to a certain extent and you will understand in the future what I mean - but if not, then why? Since we have known since the 1960s that insulinogens are not only carbohydrates. I repeat, since the 1960s. Yeah, yeah, it's the carbohydrates, isn't it? Bunch of crooks...
But I've bored you enough. I've given a lot of information for an article and I want you to digest it first.
More in the next article of this series!
Next: How our body works III >
