Insulin plays a vital role in the body’s metabolism and energy regulation. If you’ve ever wondered what does insulin do, how it relates to type 2 diabetes, or what exactly is insulin resistance, you’re in the right place. Let’s break down everything you need to know about insulin in a comprehensive yet simple way.
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What Is Insulin?
Is Insulin a Hormone?
Insulin: What Does It Do Exactly?
When Was Insulin Discovered?
Insulin for Type 2 Diabetes
What Is Insulin Resistance?
Insulin Resistance Symptoms
Insulin Resistance Diet
Insulin Resistance Treatment
What Is Insulin?
Insulin is a type of chemical messenger produced by the pancreas, a gland located behind your stomach. Specifically, insulin is made by clusters of cells known as the islets of Langerhans. So, to answer the question “where is insulin produced” — it’s produced in the pancreas!
Is Insulin a Hormone?
Yes! Insulin is a hormone that helps regulate blood sugar (glucose) levels by facilitating the uptake of glucose into the body’s cells.
Without it, the body can’t effectively manage energy, leading to serious health issues.
- High blood sugar (hyperglycemia) – the immediate result of insulin not regulating glucose levels.
- Type 2 diabetes – when insulin resistance or lack of insulin leads to chronically elevated blood sugar.
- Type 1 diabetes – an autoimmune condition where the body doesn’t produce insulin at all.
- Weight gain and obesity – insulin promotes fat storage; imbalances can lead to increased fat accumulation, especially around the belly.
- Metabolic syndrome – a cluster of conditions (including high blood sugar, high blood pressure, and high triglycerides) that increase heart disease and stroke risk.
- Fatty liver disease – excess glucose can be converted to fat in the liver, causing non-alcoholic fatty liver disease.
- Cardiovascular disease – insulin resistance is linked to high blood pressure, abnormal cholesterol levels, and artery damage.
- Nerve damage (neuropathy) – high blood sugar can damage nerves, leading to numbness, tingling, or pain.
- Kidney damage (nephropathy) – excess glucose can harm the kidneys’ filtering ability, leading to chronic kidney disease.
- Eye damage (retinopathy) – high blood sugar damages blood vessels in the eyes, increasing the risk of vision loss or blindness.
Insulin: What Does It Do Exactly?
The main insulin function is to act as a key that unlocks cells, allowing glucose from the bloodstream to enter and provide energy. When you eat carbohydrates, your body digests them into glucose, which enters your bloodstream. This raises your blood sugar levels.
But how exactly does this trigger insulin release?
Here’s what happens step-by-step:
1 – When blood sugar rises, beta cells in the pancreas detect the change.
2 – Glucose enters these beta cells through specialized channels and is used to create energy (ATP).
3 – The increase in ATP closes potassium channels in the cell, changing the cell’s electrical charge.
4 – This change opens calcium channels, allowing calcium to enter the cell.
5 – The influx of calcium causes insulin-containing vesicles to fuse with the cell membrane, releasing insulin into the bloodstream.
Once released, insulin travels through the blood and helps glucose enter muscle, liver, and fat cells. There, glucose is either used for immediate energy or stored for later.
Without insulin, glucose would stay in the blood, leading to high blood sugar levels and potential health problems like type 2 diabetes.
When Was Insulin Discovered?
Insulin was discovered in 1921 by Frederick Banting and Charles Best, with John Macleod and James Collip contributing to the discovery.
This breakthrough transformed diabetes from a fatal disease into a manageable condition.
Insulin for Type 2 Diabetes
People with type 2 diabetes often experience insulin resistance, where their body doesn’t respond properly to insulin.
This means glucose isn’t efficiently absorbed into cells, so the pancreas produces even more insulin to compensate. Over time, this extra work can exhaust the pancreas, leading to high blood sugar levels.
In many cases, insulin for type 2 diabetes is prescribed to help regulate blood sugar when diet, exercise, and oral medications aren’t enough.
What Is Insulin Resistance?
Insulin resistance happens when the body’s cells don’t respond properly to insulin. Think of it like a key that doesn’t quite fit the lock anymore—insulin is trying to open the door for glucose to enter, but the cells aren’t responding.
Insulin Resistance Symptoms
Increased hunger, because the cells aren’t getting enough energy despite high glucose levels in the blood.
Fatigue, since glucose isn’t being properly used for energy.
Difficulty losing weight, especially around the belly, due to insulin’s role in promoting fat storage.
Cravings for sugar and carbs, as the brain signals for quick energy sources.
Elevated blood sugar levels, as glucose stays in the blood instead of entering cells.
Dark patches of skin (acanthosis nigricans), caused by insulin’s effects on skin cells.
Insulin Resistance Diet
A healthy insulin resistance diet focuses on:
1. Leafy Greens
Why they help: Leafy greens like spinach, kale, and Swiss chard are high in magnesium, potassium, and antioxidants. Magnesium is crucial because it helps cells respond to insulin effectively. Antioxidants combat oxidative stress, which contributes to insulin resistance. Potassium helps regulate blood sugar and blood pressure.
Bonus nutrients: Vitamin K (supports glucose metabolism), fiber (slows digestion and sugar absorption).
2. Fatty Fish
Why they help: Salmon, mackerel, and sardines are rich in omega-3 fatty acids, which reduce inflammation. Chronic inflammation can worsen insulin resistance by interfering with insulin signaling. Omega-3s also help lower triglycerides, improving metabolic health.
Bonus benefit: Protein helps stabilize blood sugar levels by slowing carbohydrate absorption.
3. Berries
Why they help: Berries like blueberries, raspberries, and strawberries are packed with polyphenols and antioxidants that improve insulin sensitivity and reduce oxidative stress. Some studies suggest that anthocyanins in berries directly enhance insulin signaling.
Bonus nutrient: Fiber helps slow glucose absorption, reducing blood sugar spikes.
4. Whole Oats
Why they help: Oats are rich in soluble fiber, particularly beta-glucan, which slows glucose absorption and improves insulin response. This helps keep blood sugar steady and reduces the amount of insulin your body needs to produce.
Bonus benefit: Oats also promote a healthy gut microbiome, which may further support metabolic health.
5. Nuts
Why they help: Almonds, walnuts, and pistachios are high in healthy fats, fiber, and magnesium. These nutrients help reduce insulin resistance by improving cell sensitivity to insulin and stabilizing blood sugar. The fats also slow carbohydrate digestion.
Bonus nutrient: L-arginine (in nuts) supports blood vessel health, which is often compromised in insulin resistance.
Additional Foods & Compounds That Support Insulin Function
- Avocados – High in monounsaturated fats and fiber, they help stabilize blood sugar and improve insulin sensitivity.
- Cinnamon – Contains bioactive compounds that may mimic insulin’s effects and enhance glucose uptake.
- Apple cider vinegar – Can lower post-meal blood sugar spikes and improve insulin function by slowing starch digestion.
- Legumes (beans, lentils) – Packed with fiber, protein, and magnesium, which work together to improve blood sugar control.
- Green tea – Contains catechins (like EGCG) that may enhance insulin sensitivity and reduce inflammation.
- Turmeric (curcumin) – Has anti-inflammatory properties that can improve insulin signaling pathways.
- Chromium-rich foods (broccoli, eggs) – Chromium helps improve insulin action and glucose metabolism.
How They All Work Together
Fiber slows glucose absorption, reducing blood sugar spikes.
Antioxidants & anti-inflammatory compounds (like polyphenols, omega-3s) reduce chronic inflammation and oxidative stress, which disrupt insulin signaling.
Minerals like magnesium and chromium directly support insulin’s function and improve cellular response.
Healthy fats improve insulin sensitivity and slow digestion, keeping blood sugar steady.
Insulin Resistance Treatment
Insulin resistance treatment usually starts with lifestyle changes, including an insulin resistance diet, weight loss, and increased physical activity.
If lifestyle adjustments aren’t enough, medications like metformin can improve insulin sensitivity. In severe cases, insulin for type 2 diabetes may be necessary.
Conclusion
Insulin is a vital hormone with essential roles in energy regulation, glucose metabolism, and fat storage. Understanding what does insulin do, recognizing insulin resistance symptoms, and knowing how to approach an insulin resistance diet and treatment can empower you to take charge of your metabolic health.
Whether you’re curious about when insulin was discovered, where it’s produced, or how it functions, this guide provides a comprehensive overview for anyone wanting a clear and simple understanding of insulin and its effects on the body.