The Most Common Hormonal Cause of Weight Gain…

Many patients see me for hormonal concerns. One of the most common is that they’ve been having difficulty losing weight or are gaining weight unexpectedly. Most people in this situation have had their thyroid tested many times (we know hypothyroidism can lead to weight gain), but there’s another common cause that’s VERY rarely tested conventionally - and that is insulin resistance.

What is insulin?
Insulin is the hormone that allows glucose to go from the bloodstream into your cells and tissues, so they have the fuel they need to function effectively. Insulin also allows glucose to be stored when the blood sugar is high, to be used for future fueling needs. When blood sugar/glucose goes up (which it does from eating any food), your body makes insulin to send the glucose to where it needs to go and store it as needed. When you haven’t eaten in a long time - blood sugar/glucose is low, and insulin should also be low as you should no longer be processing the glucose.

What is insulin resistance, and why does it contribute to weight gain?
What happens in insulin resistance is that your cells and tissues aren’t responding to insulin as efficiently as we want them to, but your body really wants to keep your blood sugar stable still (not too high!), so you make MORE insulin to compensate for that. When insulin is elevated, it triggers your body to store! To hold onto resources for the future - contributing to weight gain. It can also have a number of other hormonal effects.

But my blood sugar is fine!
Your blood sugar (HbA1C = average blood sugar or fasting glucose) might be totally fine. Your body is making the extra insulin in order to KEEP it fine and to compensate for your cells and tissues not responding as efficiently. If this process goes unchecked for too long, though - we will eventually see prediabetes and Type II diabetes, as you can only compensate to a certain point.

How do you test for that?
The most straightforward test is to look at your fasting glucose and fasting insulin (8+ hours fasted) at the same time and then calculate the HOMA IR - the ratio between them. Remember you shouldn’t be making too much insulin when fasting as you should have already processed the sugar/glucose earlier.

What do I do about it?
The more stable we can keep your blood sugar - the less insulin you need to make. Less insulin = cells can begin to respond more efficiently. Our plan depends on the individuals’ goals, nutrition, and other symptoms but will often involve dietary changes to keep the blood sugar more stable, and sometimes supplements and/or medication to support the cells to respond to insulin more efficiently.

Insulin resistance not only impacts weight, but it can also throw off menstrual cycles, make it difficult to get and maintain pregnancy, contribute to fatigue and hair loss, and can put someone at risk of non-alcoholic fatty liver disease and diabetes. It’s a very valuable building block to assess and treat!