June 30, 2026 0 Comments

Diabetes & Insulin Resistance

Insulin Resistance Symptoms: What Your Labs Are Missing (And What to Do About It)

By Brian Lamkin DO | The Lamkin Clinic, Edmond, Oklahoma

What Is Insulin Resistance?

Insulin resistance is a condition where your cells stop responding properly to insulin, the hormone your pancreas releases to move glucose out of your bloodstream and into your cells for energy. When cells become resistant, your pancreas compensates by pumping out more insulin. For a while, blood sugar stays normal. But chronically elevated insulin drives fat storage, inflammation, hormonal disruption, and accelerated aging.

Here is the key point most people miss. The damage from insulin resistance starts long before blood sugar becomes a problem. By the time a conventional lab flags your fasting glucose or HbA1c, the process has often been running silently for years. This is why we treat it as a continuum rather than an on/off diagnosis, an approach we lay out in full in our overview of the insulin resistance spectrum.

Insulin resistance sits at the root of metabolic syndrome, type 2 diabetes, non-alcoholic fatty liver disease, and polycystic ovary syndrome (PCOS), and a growing body of research connects it to cognitive decline and cardiovascular disease. It affects an estimated 40% of American adults, most of whom have no idea. (NCBI StatPearls; NIDDK: Insulin Resistance & Prediabetes)

What Does Insulin Resistance Feel Like?

Most patients who come to The Lamkin Clinic with insulin resistance describe a collection of symptoms they have been told to write off as stress or aging. In most cases, they are neither.

The most common symptoms include:

Fatigue that does not respond to sleep. When your cells cannot use glucose efficiently, energy production breaks down at the cellular level. You sleep eight hours and wake up exhausted.

Brain fog and poor concentration. The brain is highly insulin-sensitive. Elevated insulin disrupts glucose uptake in the brain, which shows up as difficulty focusing, slow thinking, and word retrieval problems.

Stubborn belly fat. Visceral fat, the fat packed around your organs, is both a cause and a consequence of insulin resistance. Chronically high insulin tells your body to store fat rather than burn it, and the abdomen is the primary storage site. Waistlines expand even without major diet changes.

Strong sugar and carbohydrate cravings. When cells resist insulin, they are starved for fuel. The brain interprets this as a signal to seek fast glucose, which is why people with insulin resistance often feel intense cravings for bread, pasta, sweets, and soda.

Energy crashes after meals. A meal high in refined carbohydrates triggers a spike in blood sugar followed by a reactive crash as the pancreas overproduces insulin. That two-hour post-lunch slump is a metabolic signal worth paying attention to, not a normal part of the day.

Elevated triglycerides and low HDL. Excess insulin drives the liver to convert glucose into triglycerides. High triglycerides combined with low HDL is one of the most reliable early markers in routine bloodwork, and the triglyceride-to-HDL ratio is one of the most useful numbers sitting in your existing labs. (PMC: TG/HDL Ratio as a Surrogate Biomarker for Insulin Resistance)

Skin changes: acanthosis nigricans and skin tags. Darkened, velvety skin in the folds of the neck, armpits, or groin (acanthosis nigricans) reflects elevated insulin signaling in skin cells. Skin tags, small benign growths on the neck and torso, cluster strongly with metabolic dysfunction.

High blood pressure. Insulin promotes sodium retention in the kidneys, which drives up blood pressure. Many patients with hypertension of unknown cause have undiagnosed insulin resistance.

Hormonal disruptions. In women, insulin resistance drives androgen excess, which contributes to irregular cycles, hair thinning, acne, and PCOS. In men, it suppresses testosterone production, which is why testosterone optimization is often part of a complete metabolic workup. The connection between metabolic and hormonal health is direct.

Can You Have Insulin Resistance With Normal Blood Sugar?

Yes. This is where standard screening lets patients down most consistently.

A standard annual physical checks fasting glucose and sometimes HbA1c. Both measure the end-product of glucose metabolism. Neither measures insulin. A patient can have a fasting glucose of 88, well inside the normal range, while their fasting insulin is 22, driving chronic inflammation, fat storage, and hormonal disruption behind the scenes.

By the time fasting glucose rises into the prediabetic range (100 to 125 mg/dL), insulin resistance has typically been present for five to ten years. A normal glucose result is not a clean bill of health so much as a delayed warning. (NIDDK: Insulin Resistance & Prediabetes)

This is why the symptoms above matter so much. If you have three or more of them, fatigue, belly fat, brain fog, cravings, crashes, the right next step is to check the correct labs now rather than wait for blood sugar to rise.

What Labs Actually Test for Insulin Resistance?

At The Lamkin Clinic, we do not rely on fasting glucose alone. The panel that actually reveals insulin metabolism includes:

Fasting Insulin. The most direct measure. A fasting insulin above 10 µIU/mL is functionally significant, even when the lab’s reference range extends to 25. Optimal sits in the range of 3 to 7 µIU/mL. Most conventional panels never order this.

HOMA-IR. The Homeostasis Model Assessment of Insulin Resistance is calculated from fasting insulin and fasting glucose. It gives a single number that quantifies how resistant your cells are. See our full breakdown of HOMA-IR scoring. (PMC: HOMA-IR Reference Intervals)

Triglyceride-to-HDL Ratio. One of the most underused markers in a standard lipid panel. A triglyceride-to-HDL ratio above 3.0 is a strong proxy for insulin resistance, particularly in people of European ancestry, and below 1.5 is optimal. This number is already in most people’s bloodwork. It simply does not get interpreted correctly. (PMC: TG/HDL-C as the Best Surrogate Marker in Nonobese Adults, cutoff 1.5)

Fasting Glucose and HbA1c. Still useful for context, but they are late-stage markers. They confirm a problem that has already been progressing for years. We use them alongside the markers above, not in place of them.

Full metabolic panel, uric acid, and inflammatory markers. Elevated uric acid correlates with insulin resistance and gout risk. CRP and homocysteine help quantify the inflammatory burden that runs alongside it.

If your previous results came back “normal” but your symptoms have not, the issue is usually which tests were ordered. Our approach to functional lab testing is built around catching dysfunction at this earlier, more reversible stage.

What Is a Good HOMA-IR Score?

HOMA-IR is calculated as: (fasting insulin × fasting glucose) ÷ 405

Here is how to interpret your result:

HOMA-IR Score	What It Means
Below 1.0	Optimal insulin sensitivity
1.0 to 1.9	Early-stage resistance, worth addressing proactively
2.0 to 2.9	Moderate insulin resistance
3.0 and above	Significant insulin resistance, metabolic syndrome territory

Conventional labs flag resistance only above 2.0 to 2.5. A functional medicine approach treats 1.5 and up as a signal worth acting on, because the window between early and advanced insulin resistance is where intervention is most effective and most reversible. (PMC: HOMA-IR Reference Intervals)

Is Insulin Resistance the Same as Diabetes?

No. Insulin resistance is the underlying mechanism that leads to type 2 diabetes when it goes unaddressed. The two sit at different points on the same continuum, which is the core idea behind the insulin resistance spectrum.

The progression looks like this:

Insulin resistance begins. Cells stop responding normally to insulin. The pancreas compensates with higher insulin output. Blood sugar stays normal.
Prediabetes develops. The pancreas can no longer keep up. Fasting glucose climbs into the 100 to 125 mg/dL range. This stage is still fully reversible.
Type 2 diabetes. Beta cell burnout occurs. The pancreas can no longer produce enough insulin to overcome resistance. Fasting blood sugar rises above 126 mg/dL.

The critical insight is timing. Most people spend five to fifteen years in stage one before anyone catches it. Stage two remains very reversible. Stage three requires more aggressive management, though research increasingly supports reversal. (Yale School of Medicine)

Treating insulin resistance in stage one, when patients have symptoms but normal-looking labs, is one of the most impactful things a physician can do for long-term health.

How Do You Reverse Insulin Resistance?

Insulin resistance is not a permanent condition. With the right protocol, most patients see meaningful improvement in three to six months. The core interventions:

Nutrition: Reduce Insulin Load

The single most powerful dietary change is reducing refined carbohydrates and added sugars, which produce the largest insulin spikes. A low-glycemic or low-carbohydrate approach lowers fasting insulin directly.

Prioritize:

Protein at every meal (target roughly 1 g per pound of lean body mass)
Non-starchy vegetables as the carbohydrate foundation
Healthy fats: olive oil, avocado, nuts, fatty fish
Elimination of liquid calories such as juice, soda, and sweetened coffee drinks

Meal timing also matters. Extending the overnight fast to 12 to 16 hours (time-restricted eating) reduces insulin exposure and improves cellular sensitivity. Deb Lamkin, RD/LD, CDE guides patients at The Lamkin Clinic through individualized nutrition protocols built around metabolic labs rather than generic calorie targets.

Resistance Training

Skeletal muscle is the body’s primary glucose disposal site. More muscle mass means more capacity to absorb glucose without insulin. Resistance training improves insulin sensitivity acutely, within 24 to 48 hours of a session, and chronically through muscle growth over months. (PMC: Exercise and Type 2 Diabetes)

Two to four sessions per week of compound resistance training, such as squats, deadlifts, rows, and presses, produce the strongest metabolic benefit. Zone 2 cardio (sustained aerobic work at a conversational pace) complements this by improving mitochondrial function.

Sleep Optimization

A single night of partial sleep deprivation can reduce insulin sensitivity by roughly 25%. Chronic sleep debt is an independent driver of insulin resistance that nutrition and exercise cannot fully compensate for. Seven to nine hours of quality sleep is foundational for metabolic health. (Donga et al., Journal of Clinical Endocrinology & Metabolism)

Stress and Cortisol Management

Cortisol raises blood glucose directly. Chronic psychological stress produces chronic cortisol elevation, which in turn keeps insulin elevated. Patients who cannot improve metabolic markers despite excellent diet and exercise often have unaddressed HPA axis dysfunction. We evaluate cortisol as part of every metabolic workup.

Medical Intervention: When Lifestyle Needs Support

For patients with moderate to significant insulin resistance, lifestyle change alone may not be enough, or may not work fast enough. At The Lamkin Clinic, we integrate medical options when appropriate:

GLP-1 receptor agonists directly improve insulin sensitivity and are highly effective for patients with co-existing weight loss goals. We manage these as part of a comprehensive metabolic protocol rather than a standalone prescription. Learn more about GLP-1 therapy and how it compares to peptide therapy.

Metformin remains the most well-studied insulin sensitizer with an excellent safety profile, and research supports its use in prediabetic patients alongside lifestyle change. (Diabetes Prevention Program / DPPOS review)

Berberine and inositol are well-evidenced nutraceutical options that improve insulin signaling and are appropriate for early-stage resistance.

Hormone optimization. Low testosterone in men and hormonal imbalance in women both worsen insulin resistance independently. Correcting underlying hormonal dysfunction through hormone optimization is often a necessary part of a complete metabolic protocol.

The Lamkin Clinic Approach

Most patients who come to us with insulin resistance have already been told their labs are normal. They are not imagining the fatigue, the belly fat, or the brain fog. In most cases, the right labs simply were not ordered.

We run a complete metabolic panel, including fasting insulin, HOMA-IR, triglyceride-to-HDL ratio, a full hormone panel, and inflammatory markers, then build a personalized protocol from those results. The plan addresses the actual drivers of your metabolic dysfunction rather than offering a generic recommendation to eat less and move more.

Insulin resistance caught early is highly reversible. There is no reason to wait for a diabetes diagnosis to take it seriously.

Ready to understand what your labs are actually telling you? Request an appointment with Dr. Brian Lamkin at The Lamkin Clinic.