Does Insulin Cause Weight Gain?

Let's settle this debate once and for all: Does insulin cause weight gain? 

The answer is a resounding NO…

Now, I know there will be people who strongly agree or disagree with me on this matter. Some might argue that their doctors have told them otherwise. But have you ever stopped to think for yourself and question the information presented to you?

Let's dive into the topic.

Insulin itself does not cause weight gain. The real culprit behind weight gain is consuming too many calories, which then get stored as body fat. Insulin can play a role in facilitating this process, but it is not the underlying cause. 

Think of calories as raw materials for your body, just like wood, steel beams, and concrete are for building a house. You have inputs (calories) and outputs (energy expenditure). If you consume an excess of calories, your body will store them as fat. 

On the other hand, if you don't consume enough calories, you'll be in a calorie deficit, and your body won't have anything to store. 

Claiming that insulin causes weight gain is like saying you can build a roof out of thin air—it simply doesn't make sense.

Now, you may argue, "But when I was diagnosed with diabetes and started taking insulin, I gained 30 pounds!" Yes, it's entirely possible that you gained weight. And yes, insulin may have contributed to it.

However, insulin is not the reason you gained those pounds. Here's what likely happened: 

Prior to your diagnosis, your body was not producing enough insulin, so the glucose from the food you consumed was not being properly processed. Instead, it was being excreted through frequent urination. Your body couldn't use that fuel because insulin acts as the key to unlock cells and allow energy to enter. Without enough insulin, the glucose remains in your body, leading to inadvertent calorie deficit. You may have been eating 2,000 calories a day, for example, but your body could only process, let's say, 400 calories. That means you were in a 1,600 calorie deficit—a significant amount. Consequently, you experienced rapid weight loss.

When you introduced insulin into the equation, it allowed your body to utilize the energy it was previously excreting. Suddenly, those 1,600 calories you were wasting became available for your body to use. From your body's perspective, it was receiving a surplus of energy because it had grown accustomed to absorbing only 400 calories. So, it may appear that you're gaining weight, but in reality, you're regaining the weight you had lost due to the initial calorie deficit. Insulin is not causing weight gain; it's simply enabling your body to utilize the nutrients you're consuming.

Weight gain is ultimately determined by the balance between calories consumed and calories expended. While there are other factors at play, insulin is not the reason for weight gain. However, it's essential to note that there are alternative methods, such as the action of Acylation-Stimulated Protein (ASP), which can contribute to weight gain in an excess calorie state without relying on insulin. Your body has backup mechanisms to store body fat when the primary pathway faces obstacles.

So, to conclude, insulin does not cause weight gain.

I hope this explanation clarifies the relationship between weight gain and insulin for you.

Feel free to share your experiences and comments below. If you have further questions or specific topics you'd like to learn about, let us know.

Our team of dietitians are always willing to answer your questions.