What Your Doctor Probably Didn’t Explain About Insulin Resistance

The Explanation I Didn’t Get

When I was diagnosed with prediabetes in early 2023, the explanation I received was brief and familiar. My A1C was elevated. I should watch my carbs, lose some weight, exercise more, and come back in three months. There was a pamphlet involved.

That explanation wasn’t wrong. But it was incomplete in ways that cost me a full year of confusion and misplaced effort.

What I wasn’t told, and what I had to discover through my own research, a continuous glucose monitor, and a lot of trial and error, is that insulin resistance is far more complex than a simple input-output equation of carbs and glucose. The factors that drive insulin resistance include things most doctors don’t have time to discuss in a fifteen-minute appointment. And some of those factors have nothing to do with food at all.

This is what I wish someone had explained to me from the beginning.

Insulin Resistance: The Actual Mechanism

Most explanations of insulin resistance stop at “your cells don’t respond to insulin as well as they should.” That’s technically accurate. But it’s a bit like saying a traffic jam happens because cars aren’t moving. It doesn’t tell you why.

Here’s what’s actually happening. Your body produces insulin to help move glucose from your bloodstream into your cells, where it gets used for energy. When everything works well, a moderate amount of insulin does the job efficiently. Your blood sugar stays in a healthy range. The system is in balance.

In insulin resistance, your cells become less responsive to insulin’s signal. The pancreas compensates by producing more insulin. For a while, this works. Blood glucose stays normal because the pancreas is working overtime. But the excess insulin circulating in your body has effects of its own: it promotes fat storage (particularly around the abdomen), increases inflammation, and can worsen the very resistance it’s trying to compensate for.

By the time your A1C rises enough to trigger a prediabetes diagnosis, this cycle has often been running for years. The A1C test often catches the problem late. And the standard advice to “cut carbs and exercise” addresses one input in a multi-input system.

The Stress Factor Nobody Warned Me About

This is where my own experience taught me something the pamphlet couldn’t.

We all know stress is bad for health in a general, vague way. What I didn’t understand was the specific, measurable connection between stress and glucose. Until I saw it happen in my own body.

My husband was in for eye surgery. A nurse came out to update me in the waiting room. Complications. The kind of update that makes your stomach drop. I stayed calm on the outside. Asked questions. Sat back down. And then quietly started falling apart on the inside.

A few minutes later I glanced at my continuous glucose monitor. My glucose had spiked above 200. I hadn’t eaten anything.

What was happening is straightforward physiology. When your body perceives a threat, whether it’s a bear in the woods or terrifying news in a hospital waiting room, your adrenal glands release cortisol and adrenaline. These hormones signal your liver to dump stored glucose into the bloodstream. It’s your body’s emergency fuel system, designed to give your muscles the energy to fight or flee.

The problem is that your body doesn’t distinguish between physical danger and emotional distress. The same stress hormones fire. The same glucose release happens. And if you’re already insulin resistant, your cells can’t clear that glucose efficiently. So it sits in your bloodstream, spiking your levels, even though you haven’t eaten a thing.

This isn’t an edge case. Chronic stress, the kind most of us live with daily in some form, keeps cortisol elevated over time. And chronically elevated cortisol doesn’t just spike glucose in dramatic moments. It steadily worsens insulin sensitivity, promotes inflammation, disrupts sleep (which further worsens insulin resistance), and creates a feedback loop that diet changes alone can’t break.

When I learned this, a lot of things started making sense. Why my glucose was sometimes high on mornings after stressful days, even when I’d eaten well. Why periods of high work pressure coincided with worse lab results. It also reframed relaxation and recovery as actual medical interventions, not luxuries.

The Stress You Don’t Recognize as Stress

This is where it gets tricky. Because when most people hear “manage your stress,” they think about meditating, taking a vacation. Those things matter. But there are forms of stress that affect insulin resistance that don’t feel like stress at all.

Oxidative stress from overtraining. If you’re exercising intensely every day without adequate recovery, you’re generating oxidative stress that increases inflammation and can worsen insulin sensitivity. The irony is that exercise is one of the best things for insulin resistance, but too much of it, without recovery, does the opposite. I learned this when I noticed my glucose was higher on mornings after consecutive hard workouts than after rest days.

Inflammatory stress from food. Some foods that seem perfectly fine, foods that don’t trigger obvious symptoms, can create a low-grade inflammatory response in your body. This inflammation contributes to insulin resistance. It’s individual and often invisible. You might feel nothing and still be triggering a glucose response that undermines your efforts.

Sleep deprivation. Even one night of poor sleep measurably reduces insulin sensitivity. Chronic poor sleep is one of the most potent drivers of insulin resistance, and it’s one of the least discussed in standard medical conversations about prediabetes. I started paying attention to my glucose on mornings after bad sleep and the pattern was unmistakable.

Chronic cognitive load. The mental effort of managing a complex life, juggling work, family, health management, financial concerns, doesn’t register as “stress” in the way most people understand the word. But your body responds to sustained cognitive demand the same way it responds to other stressors. Cortisol rises. Glucose follows.

What This Means for Managing Insulin Resistance

If insulin resistance were purely about carbohydrate intake, the solution would be simple: eat fewer carbs. For some people, that helps significantly. But if you’ve tried dietary changes and your numbers aren’t responding the way you expected, it’s worth looking at the rest of the picture.

Recovery matters as much as exercise. I now build recovery days into my workout schedule the same way I build strength days. They’re not optional or lazy. They’re physiologically necessary for keeping inflammation in check and supporting insulin sensitivity.

Stress management is a glucose management strategy. I came into my prediabetes journey thinking breathwork and meditation were nice-to-haves. I now understand them as directly connected to my metabolic health. When I’m consistent with stress-reducing practices, I see it in my numbers. When I slack off, I see that too.

Sleep is non-negotiable. I’ve reorganized my evenings around protecting sleep. I extended my bedtime routine. I gave myself permission to go to bed “early” without apologizing for it. The impact on my morning glucose readings was significant.

And perhaps most importantly: I stopped expecting my glucose to behave like a simple equation and started seeing it as information about my entire life, not just my meals. And that shift in perspective reduced the shame and self-blame that were themselves a source of stress, feeding the very cycle I was trying to interrupt.

The Bigger Picture

None of this is meant to dismiss the importance of nutrition. What you eat matters. Carbohydrate quality and quantity affect glucose. Building meals around protein, healthy fats, and fiber makes a real difference. I’ve experienced all of that firsthand.

But nutrition is one input in a complex system. And when doctors hand patients a pamphlet about carbs and send them home, they’re addressing one variable while leaving the others unspoken. Stress, sleep, recovery, inflammation, mental load, emotional health. These aren’t secondary concerns. They’re central to how insulin resistance works and how it resolves.

I wish someone had told me this three years ago. It would have saved me a year of misplaced guilt and the exhausting belief that I just wasn’t trying hard enough.

If you’re navigating insulin resistance or prediabetes and feeling like the standard advice isn’t adding up, the full picture might be what’s missing.