PCOS and Insulin Resistance

Think insulin only matters if you have diabetes? Think again.

Insulin affects nearly every system in your body, from weight and mood to fertility and aging. In fact, 88% of U.S. adults show signs of insulin resistance, even if they feel “healthy.”

At Lilli Health, we believe insulin should be a household word. That’s why we’re here: to teach you how insulin works, why it matters, and how a Low Insulin Lifestyle can help you feel better, look better, and live longer.

Understanding insulin isn’t just for diabetics—it’s for everyone. And it’s simpler than you think.

What You'll Learn with Lilli

What Is Insulin Resistance?

Why your body is storing fat instead of burning it.

Insulin resistance happens when your cells stop responding (X) properly to insulin (🗝️), the hormone that helps move sugar (⬜) out of your blood and into your cells.

In response, your body produces even more insulin (a state called hyperinsulinemia), which leads to stubborn weight gain (especially around the belly), constant fatigue, cravings, and inflammation.

Here’s the tricky part: you can’t always detect insulin resistance by measuring blood sugar or wearing a CGM. Your glucose may look “normal” for years while insulin levels stay high behind the scenes, silently driving weight gain, hormone issues, and disease risk.

Most people don’t realize they’re insulin resistant until serious symptoms show up, and by then, their metabolism is already working against them.

What Causes Insulin Resistance?

Insulin resistance doesn’t happen overnight—it builds over time from repeated spikes in insulin.

Every time you eat, especially foods that are high in sugar or starch, your pancreas releases insulin to help move that sugar into your cells. But when you’re eating foods that spike insulin multiple times a day—day after day—your cells start tuning it out.

This is known as receptor downregulation—your body’s way of saying, “I’ve had enough.” In response, your pancreas produces even more insulin to force the signal through. Over time, this leads to chronically high insulin levels, or hyperinsulinemia, which is the driver behind fat storage, inflammation, and hormone disruption.

The biggest culprits?

Starch
Sugar
Non-fermented Dairy

You don’t have to have high blood sugar to have insulin resistance. In fact, your blood sugar can remain normal for years while insulin levels stay elevated, causing damage.

The good news? This process is reversible. And it starts with reducing the frequency and intensity of insulin spikes. This is the basis behind a Low Insulin Lifestyle.

Why Diets Don't Work

Why Standard Nutrition Advice Fails

“Eat less, move more” isn’t working—and here’s why.

Most traditional diets focus on reducing calories or carbs, but they miss the bigger picture: insulin. Insulin is the hormone that tells your body whether to store or burn fat. If your insulin is high, your body stays in fat-storage mode, no matter how few calories you eat or how much you exercise.

Even common “health foods” like brown rice, certain types of dairy, and granola can spike insulin and keep you stuck. That’s why so many people feel like they’re doing everything right but still can’t lose weight, improve their symptoms, or feel better.

A Low Insulin Lifestyle addresses the real root cause.

The Master Hormone: Insulin

The Hormone That Drives Everything from Weight to Mood

Insulin isn’t just about blood sugar. It’s one of the body’s most powerful hormones, and it affects nearly everything: your energy, your skin, your hunger cues, your periods, your fertility, your sleep, and even how quickly you age.

When insulin levels are high, it doesn’t just store fat; it disrupts the entire hormonal ecosystem. It can increase testosterone (causing acne, hair loss, and irregular cycles), lower estrogen and progesterone (impacting fertility), dysregulate cortisol (spiking stress and anxiety), affect your thyroid (slowing your metabolism), and interfere with leptin (your hunger/fullness signal).

In short: insulin is upstream of almost every other hormone. If your insulin levels are out of balance, your entire system feels off—physically, mentally, and emotionally.

That’s why lowering insulin is one of the most effective root-cause approaches to improving your health.

The PCOS Connection

PCOS isn’t a reproductive disorder; it’s a metabolic one.

When insulin levels are high, they tell your body to make more testosterone. That’s what leads to so many frustrating PCOS symptoms, such as acne, hair thinning, excess facial hair, irregular periods, weight gain, and trouble getting pregnant. These symptoms are just the result of something deeper going on.

The real cause? Too much insulin.
And the only way to truly treat PCOS is to lower insulin levels. Full stop.

You can take birth control, spironolactone, or fertility meds, and they might help for a while, but they don’t fix the root problem. Unless you bring insulin levels down, those symptoms will keep coming back.

The good news? You can lower insulin naturally.

When you start eating in a way that reduces insulin spikes, your body can begin to reverse insulin resistance. You might start ovulating again. You might lose weight. Your skin might clear up. Your cravings might fade. And you may finally feel like yourself again.

PCOS starts with insulin. That’s why Lilli starts there, too.

Fasting Insulin: 3-8 mIU/ml

Fasting insulin greater than 8 mIU/ml suggests insulin resistance

HOMA-IR: ≤ 1.9

HOMA-IR score greater than 1.9 suggests insulin resistance

Ideally, a fasting insulin should be between 3-8 mIU/ml (50 pmol/L), but what is considered “normal” varies by lab. It may surprise you to know that some labs define a wide range of 3-30 mIU/ml as normal, which is quite concerning. Research studies have consistently shown that fasting insulin levels above 8 mIU/ml are associated with insulin resistance and an increased risk of developing chronic diseases.

Despite the significant impact of insulin on the development of chronic diseases, it’s unfortunate that measuring insulin levels is not a routine practice among healthcare providers. Usually, only blood glucose levels or hemoglobin A1c are measured, which solely provide information about elevated blood glucose levels. This is why I cringe when I hear the phrase “balance your blood sugar.” A “balanced” or “normal” blood sugar reading doesn’t provide insight into your insulin levels. Surprisingly, certain foods with no carbohydrates can still significantly impact insulin levels. That’s why it’s more accurate and beneficial to focus on “lowering your insulin levels” rather than solely aiming for blood sugar balance. By addressing insulin levels, we can not only resolve blood sugar problems but also address the underlying issues caused by elevated insulin levels. It’s a more comprehensive approach to improving overall health.

Overall, it’s important to recognize that insulin plays a crucial role in overall health, especially when it comes to conditions like insulin resistance and PCOS. Therefore, it is valuable to advocate for more comprehensive testing that includes measuring insulin levels, as it provides a more complete picture of your metabolic health and helps guide appropriate interventions to manage insulin-related issues effectively.

Fortunately, we will soon offer the convenience of purchasing an insulin testing kit directly from our website! With this kit, you can easily measure your insulin levels and HOMA-IR in the comfort of your own home. It’s a simple and effective way to gain valuable insights into your insulin status and take control of your health. By understanding your insulin levels, you can make informed decisions and tailor your lifestyle choices to support optimal insulin function.

Are You Insulin Resistant?

The symptoms and labs most people (and even doctors) overlook.

You don’t have to be diabetic, or even have high blood sugar, to be insulin resistant. In fact, insulin resistance often goes undetected for years because standard lab tests like glucose and A1c can still look “normal” in the early stages.

But your body may already be showing signs.

Common symptoms include:

Weight gain, especially around your belly
Trouble losing weight despite “doing everything right”
Feeling tired or sluggish
Strong carb or sugar cravings
Irregular periods or difficulty conceiving
Brain fog or poor concentration
Skin tags or dark patches on the neck or underarms

More accurate labs include fasting insulin, HOMA-IR, and C-peptide, tests that measure how hard your body is working to keep blood sugar in check. These can reveal insulin resistance long before it shows up on standard glucose or A1c labs.

If you’ve been told “everything looks fine,” but you still feel off—this is probably why.

References

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