Insulin Resistance--An Important Disease Predictor
What is insulin?
Insulin is one of the most important biomarkers which can help detect adverse underlining metabolic changes and predict chronic diseases 10-15 years earlier.
Insulin is a hormone produced by the pancreas that plays a crucial role in regulating blood sugar (glucose) levels. Its main functions include:
1. Blood Sugar Regulation
When you eat, carbohydrates are broken down into glucose, which enters the bloodstream.
In response, the pancreas releases insulin to help move glucose into cells for energy or storage.
2. Energy Storage & Usage
Immediate Energy: Insulin allows cells (especially muscle and brain cells) to absorb glucose and use it for energy.
Storage Mode: If there's excess glucose, insulin signals the liver and muscles to store it as glycogen for later use.
Fat Storage: If glycogen stores are full, insulin helps convert extra glucose into fat for long-term storage.
3. Prevents Excessively High Blood Sugar (Hyperglycemia)
Without enough insulin, glucose stays in the blood, leading to high blood sugar levels (a hallmark of diabetes).
4. Helps Maintain Overall Metabolic Balance
Insulin also influences fat and protein metabolism, affecting muscle growth, fat storage, and even inflammation.
What is Insulin resistance?
According to information from the NIH website, insulin resistance is a condition in which the body's cells—primarily in the liver, muscle, and adipose tissue—become less responsive to insulin. This impairs glucose uptake, leading to compensatory overproduction of insulin (hyperinsulinemia) by the pancreas. Over time, insulin resistance can contribute to elevated blood sugar (hyperglycemia), high blood pressure, abnormal lipid levels (dyslipidemia), elevated uric acid (hyperuricemia), inflammation, endothelial dysfunction, and increased blood clot risk (prothrombotic state).
The most significant consequence of insulin resistance is type 2 diabetes (T2D), which may develop 10 to 15 years after its onset. Lifestyle interventions are the first line of treatment, with a focus on nutritional changes, including calorie reduction and limiting high-glycemic carbohydrates to reduce insulin demand. Regular physical activity improves insulin sensitivity by enhancing glucose uptake in skeletal muscle.
Complications of insulin resistance primarily involve vascular diseases and nonalcoholic fatty liver disease (NAFLD), both of which increase the risk of metabolic and cardiovascular disorders. Moreover, insulin resistance can lead many other diseases as well including kidney disease, eye disease, cancer, Alzheimer's, PCOS, sleep apnea, etc.
Fasting Insulin Reference Ranges
Optimal Range: 2–6 µIU/mL (varies slightly by lab)
Borderline/Moderate Insulin Resistance: 6–12 µIU/mL
High/Significant Insulin Resistance: >12 µIU/mL
Fasting insulin is such a key biomarker that everyone should know their level.
What Elevated Fasting Insulin Means
Elevated fasting insulin can be an early sign of insulin resistance, even if your fasting glucose and HbA1c are still normal. Insulin resistance is a key driver of metabolic dysfunction, including:
Weight gain (especially around the midsection)
Increased risk for Type 2 Diabetes
Dyslipidemia (high triglycerides, low HDL cholesterol)
Elevated inflammation and cardiovascular risk
Steps to Consider
Elevated fasting insulin can be caused by multiple factors, including diet, sleep, stress, heavy metals, and other toxic elements. To address an elevated fasting insulin level, here are actionable strategies that can help with all the above causes:
Diet:
Focus on a low-glycemic, nutrient-dense diet (e.g., whole foods, high fiber, healthy fats, quality proteins).
Reduce or eliminate refined carbs and sugar.
Exercise:
Incorporate both resistance training and aerobic activity to improve insulin sensitivity.
Sleep:
Aim for 7–8 hours of quality sleep, as poor sleep can worsen insulin resistance.
Stress Management:
Practice stress-reducing activities like mindfulness, yoga, or meditation.
Monitor:
Test related markers like fasting glucose, HbA1c, triglycerides, and HOMA-IR for a fuller picture.
Actionable strategies to improve insulin sensitivity
1. Nutrition Strategies
a. Focus on a Low-Glycemic, Whole-Foods Diet
Prioritize foods that have a minimal impact on blood sugar levels:
Proteins: Grass-fed meats, pasture-raised poultry, wild-caught fish (salmon, sardines), and eggs.
Fats: Avocados, olive oil, nuts (almonds, walnuts), seeds (chia, flax, hemp), and fatty fish.
Carbohydrates:
Non-starchy vegetables: Broccoli, spinach, kale, cauliflower, zucchini, asparagus, etc.
Low-glycemic fruits: Berries, cherries, green apples, and citrus fruits (in moderation).
Small portions of whole, unprocessed carbs: Quinoa, sweet potatoes, and wild rice.
Fiber-Rich Foods: Artichokes, Brussels sprouts, flaxseed, chia seeds, and psyllium husk.
b. Avoid Blood Sugar Spikes
Limit or avoid refined carbs (white bread, pastries, sodas).
Pair carbs with protein or healthy fats to reduce their glycemic impact.
Avoid sugary drinks and juices; opt for water, herbal teas, or black coffee.
c. Time Your Meals
Try intermittent fasting (IF) or extend the overnight fasting window to 12–16 hours, if appropriate for your health and lifestyle. This helps reset insulin sensitivity.
Avoid late-night eating, as it can increase insulin levels.
d. Incorporate Anti-Inflammatory Foods
Spices: Turmeric (with black pepper), cinnamon, and ginger.
Omega-3s: Fatty fish or a high-quality fish oil supplement.
Polyphenol-rich foods: Green tea, dark chocolate (85%+), and extra virgin olive oil.
2. Lifestyle Adjustments
a. Prioritize Movement
Many types of exercise can help improve insulin sensitivity, including aerobic exercise, resistance training, and high-intensity interval training (HIIT)
Combining aerobic and resistance exercise can produce the greatest effect on insulin sensitivity.
Find an exercise you enjoy so you're more likely to stick with it.
Exercise regularly throughout your life.
b. Manage Stress Levels
Chronic stress increases cortisol, which worsens insulin resistance.
Practice mindfulness: Daily meditation or deep breathing exercises.
Engage in relaxing hobbies: Gardening, journaling, or yoga.
c. Get Quality Sleep
Aim for 7–8 hours of restorative sleep each night.
Create a sleep routine: No screens 1–2 hours before bed, a cool dark room, and a consistent schedule.
3. Supplement Support
Consider these with guidance from a healthcare provider:
Berberine: Improves insulin sensitivity and reduces fasting insulin.
Magnesium: Supports glucose metabolism. Opt for magnesium glycinate or citrate.
Alpha-Lipoic Acid (ALA): Enhances insulin function and reduces oxidative stress.
Chromium Picolinate: Helps regulate blood sugar.
Probiotics: Supports gut health, which is linked to insulin sensitivity.
4. Track Progress
Recheck fasting insulin in 2–3 months.
Monitor additional metrics: fasting glucose, HbA1c, triglycerides, and waist circumference.
References