Insulin Resistance & Prediabetes

Insulin Resistance and Prediabetes, Explained

Insulin resistance and prediabetes affect a huge number of adults, and most of them don't know it. Here's what these terms actually mean, why they usually cause no noticeable symptoms, and why getting screened matters far more than any supplement on the market.

What is insulin resistance?

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) defines insulin resistance directly: "Insulin resistance is a condition in which your body doesn't respond to insulin the way it should." In practice, that means your pancreas is releasing insulin as normal, but your muscle, fat, and liver cells aren't taking up glucose from the blood as efficiently as they should in response. To compensate, the pancreas produces more insulin to try to keep blood glucose in range. For a while, that compensation can keep blood sugar looking normal on a test — but it comes at the cost of the pancreas working harder than it should have to, and over time it may not be able to keep up.

What is prediabetes?

Prediabetes is the next stage in this progression. According to NIDDK, "people have prediabetes if they have blood glucose levels that are higher than normal but not high enough to be diagnosed as type 2 diabetes." In other words, it's a measurable, in-between zone — not yet diabetes, but no longer normal — that reflects the pancreas starting to lose the battle against insulin resistance. It's diagnosed through standard blood tests, not by symptoms, which leads to the single most important fact on this page.

The symptom that usually isn't there

Most people with prediabetes feel completely normal NIDDK states plainly: "People with insulin resistance and prediabetes usually have no symptoms." There's no distinct feeling of "getting insulin resistant." This is exactly why prediabetes is so often missed — there's no obvious warning sign prompting someone to see a doctor, so it's typically found only through blood tests like fasting glucose or HbA1c, often ordered as part of routine bloodwork or screening for other reasons.

This absence of symptoms is arguably the most practically important fact about insulin resistance and prediabetes: you cannot rule it out just because you feel fine. Feeling energetic, sleeping normally, and having no unusual thirst or fatigue does not mean your blood glucose regulation is working the way it should.

How common is this?

This isn't a rare condition. NIDDK reports that "in 2021, about 97.6 million people in the United States ages 18 and older had prediabetes." That's a substantial share of the entire U.S. adult population — meaning insulin resistance and prediabetes are, statistically, far more likely to be present in any given adult than most people assume, precisely because it so often produces no symptoms to prompt concern.

Why screening matters more than any supplement

Because prediabetes and insulin resistance are largely silent, the only reliable way to know where you stand is through actual blood testing ordered and interpreted by a healthcare professional — not through how you feel, and not through trying a supplement to see if you "notice a difference." A supplement cannot diagnose insulin resistance, and improvement (or lack of it) while taking one tells you very little, since you likely didn't know your baseline numbers to begin with. The NCCIH's review of dietary supplements for diabetes makes a directly relevant point: "It's very important not to replace medical treatment for diabetes with an unproven health product or practice." Screening — through your doctor, not through a bottle — is the step that actually catches this early, when lifestyle changes and medical management are most effective.

If you're evaluating a product like Sugar Defender in this context, it's worth being clear-eyed about what it is and isn't: a dietary supplement marketed for blood sugar support, not a diagnostic tool and not a substitute for screening or prescribed treatment. We break down what's actually in the formula on our ingredients page and what's verified versus claimed on our how it works page.

Related reading

For the basics of how blood glucose and insulin work day to day, see our blood sugar guide. For medication interaction cautions relevant to anyone managing insulin resistance or diabetes who is considering a supplement, see our safety & side effects page.

Sources

Frequently asked questions

What is insulin resistance?

According to NIDDK, insulin resistance is a condition in which your body doesn't respond to insulin the way it should, meaning cells take up less glucose from the blood even though insulin is present and signaling them to.

Does prediabetes have symptoms?

Usually not. NIDDK states that people with insulin resistance and prediabetes usually have no symptoms, which is exactly why screening through blood tests, rather than waiting to notice something wrong, is how it's typically found.

How common is prediabetes?

According to NIDDK, in 2021 about 97.6 million people in the United States ages 18 and older had prediabetes.

Continue reading: Blood sugar basics · How Sugar Defender claims to work · Safety & side effects