Insulin and glycemic index for weight loss: are they important or not?

Author: Mikhail Ziborov - author of the site makefitness.pro.
2023-06-29

There used to be more, but even now, there are quite a few people who claim that insulin is the reason for gaining excess weight. It's like, you eat, insulin is produced, and it starts transporting nutrients to fat cells (which is supposedly why we get fat). But is it really true?

For those interested in the topic of weight loss, I recommend our Telegram channel. We publish concise and specific information on weight loss and everything related to it daily.

Insulin for Weight Loss

Briefly about the issue: many Instagram bloggers, various self-styled experts, and even trainers who have read those "smart" people believe that insulin is the culprit of excess weight. And that the glycemic index of food affects the speed of weight accumulation. It is as if eating foods with a low glycemic index means we won't gain fat. Look.

Insulin is a hormone that does indeed influence fat storage, and it indeed inhibits lipolysis (the breakdown of fatty acids and their release into the blood for further burning, i.e., weight loss).

But insulin only stores fat when there's something to store! That is, when we eat a lot and take in more calories than our body needs. Only in this case will insulin promote the growth of subcutaneous fat tissue.

If you control the number of calories consumed in a day, you won't gain excess weight. Despite insulin levels rising sky-high. In one case (with a calorie surplus), insulin increases and stores fat; in another case (with a calorie deficit), insulin increases but does not store fat because there’s nothing to store.

You cannot store excess weight when you are in a state of energy (calorie) deficiency! Although insulin increases in both cases.

The increase in subcutaneous fat depends not on insulin and its level in the blood, but on how much you eat. Weight loss is not dependent on insulin.

How does insulin work in the body? Insulin rises due to the amount of glucose in the blood: you eat a lot of fast carbs, glucose enters the blood—insulin spikes, trying to transport glucose to its storage sites (it is, among other things, a transport hormone).

And this is what scares people, saying that if insulin is high, you will gain fat (I dare not use the word). However, those same people advise eating more protein: protein indeed helps with weight loss. They just forget that insulin also rises when we eat protein.

So, if you eat carbs and insulin is high, you will get fat, but if you eat protein, insulin will also be high, but you won’t get fat. Clearly, this is not an issue of insulin, since in both cases it’s high, but we don’t gain weight in both cases.

Glycemic Index and Weight Loss

The glycemic index (GI) is an indicator of the increase in blood glucose levels. The higher this indicator, the more glucose is present in the blood plasma. For example, the GI of cabbage is 20, buckwheat is 54, and table sugar (the kind we add to tea) is 110.

It is clear that sugar raises blood glucose levels more than buckwheat or cabbage. And the more glucose in the blood, the more insulin is needed. But all this does not influence weight loss in any way.

Look. Suppose you eat only high-glycemic index foods. Because of them, your insulin levels will spike (insulin is responsible for distributing glucose from the blood to tissues and organs). But if you are consuming fewer calories than your daily requirement from these high-glycemic foods, there will be no fat gain.

For one simple reason: you are in a state of energy deficit; your body has no resources to build reserves. It’s like trying to save money when you can’t even afford food and utilities. There’s no ability to save. And the speed at which you receive this money (glycemic index), how quickly you spend it (the action of insulin), will not affect the amount of money in your savings (fat reserves).

The glycemic index was invented solely for people with health problems (specifically, for diabetics, who need to know their blood glucose levels). But modern self-proclaimed experts use tools designed for the sick on healthy individuals.

Moreover, we don’t eat pure sugar (where GI is high, and insulin spikes), but mixed products. If you eat two products—one with a high GI and another with a low GI—you will get an average GI level. That is, insulin and blood glucose levels will not increase so drastically.

Conclusion

Undoubtedly, if you eat only high-glycemic index products, keeping insulin levels high at all times, you could even develop type 2 diabetes, even with a low percentage of body fat. Yes, health problems can develop. But right now we are talking not about health but about weight loss and excess weight.

However, insulin and glycemic index are not the variables that influence the percentage of subcutaneous fat. The amount of excess weight you have depends on the number of calories consumed daily. For example, if you follow a meal plan, excess weight will not be a problem for you.