Fasting Insulin: An underestimated ally against obesity

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tl;dr

1. Fasting insulin levels provide a valuable glimpse into your metabolic health and insulin sensitivity, indicating how effectively your body regulates blood sugar.

1. Higher fasting insulin levels, often associated with insulin resistance, are linked to a higher risk of various metabolic disorders and even mortality. It's important to monitor insulin levels for tailored solutions for preventive health care.
2. Have you had your fasting insulin tested and interpreted? Book a blood test here and meet me for the next steps in your longevity journey.

1. Fasting insulin levels provide a valuable glimpse into your metabolic health and insulin sensitivity, indicating how effectively your body regulates blood sugar.

1. Higher fasting insulin levels, often associated with insulin resistance, are linked to a higher risk of various metabolic disorders and even mortality. It's important to monitor insulin levels for tailored solutions for preventive health care.
2. Have you had your fasting insulin tested and interpreted? Book a blood test here and meet me for the next steps in your longevity journey.

Longevity Lesson

Thanks to pop health influencers, first-hand experience, and general awareness of common health issues, most of us are familiar with the idea that diabetes and obesity share a connection with the hormone insulin. But did you know that there are multiple ways to measure and assess your insulin levels? Today we’re going to take a closer look at fasting insulin and explore what it means for our health and longevity.

Fasting insulin is a blood test that measures your insulin levels after a period of fasting (around 8-12 hours without eating). It offers valuable insights into metabolic health and insulin sensitivity. High insulin levels during fasting suggest that your body is struggling to regulate blood sugar effectively, a hallmark of insulin resistance—a precursor to type 2 diabetes. Conversely, lower fasting insulin levels indicate better insulin sensitivity, meaning cells respond efficiently to insulin signals to absorb glucose, promoting stable blood sugar levels. Monitoring fasting insulin helps you assess your risk of developing diabetes and obesity and make informed choices about lifestyle interventions to improve metabolic health.

Why care about fasting insulin?

The facts paint a concerning picture of metabolic disorders, including obesity and diabetes.

• Higher fasting insulin and c-reactive protein levels are linked to an increased risk of all-cause mortality, complicating the BMI-mortality relationship.
• Insulin resistance, rather than obesity itself, is often the primary driver of type 2 diabetes, cardiovascular disease, and cancer, with compensatory hyperinsulinemia following.
• Lifestyle factors that raise diabetes risk are associated with higher basal insulin levels, predicting future obesity in youth.
• Reducing insulin secretion through medication helps obese patients lose weight. Elevated insulin levels cause weight gain by stopping fat breakdown and encouraging fat storage.
• While diabetes results from insufficient insulin action, obesity and type 2 diabetes can coincide with elevated insulin levels, termed hyperinsulinemia.

Get your fasting insulin levels tested and interpreted by Dr. Marcus. Book a blood test here.

Harnessing fasting insulin for tailor-made health interventions

Regularly measuring your fasting insulin levels can provide valuable insights into your metabolic health and weight gain susceptibility. This allows for tailored, personalised approaches to nutrition and lifestyle interventions to prevent and manage obesity. People with higher fasting insulin levels may benefit from dietary approaches that prioritise low-glycemic index foods that help stabilise blood sugar levels and reduce insulin secretion. Additionally, focusing on nutrient-dense, whole foods over processed options can support metabolic health and aid in weight management. Lifestyle interventions, such as regular physical activity and stress management techniques, can also be tailored based on your fasting insulin levels. Exercise has been shown to improve insulin sensitivity, while stress reduction techniques can help mitigate the cortisol response, which can contribute to insulin resistance and weight gain. 

Longevity Homework

Stay on top of your fasting insulin

There are several simple and sustainable measures we can take to manage our fasting glucose levels. These span every area of life including balanced nutrition, healthy lifestyle habits, sleep hygiene and increased physical movement. But all of these measures vary from person to person, based on their individual needs and fasting insulin levels. Read on for a snapshot of the various ways in which fasting insulin is measured and how the results can be interpreted.

What you need to know first:

• Get your fasting insulin levels tested after an overnight fast (8-12 hours without eating).
• Normal fasting insulin levels range from 2.6-24.9 μIU/mL.
• Elevated fasting insulin levels indicate insulin resistance, even if fasting glucose levels are normal. Higher insulin levels suggest the body is struggling to regulate blood sugar, a sign of insulin resistance.
• Research links fasting insulin levels over 7 mcIU/ml to a significant increase in the risk of metabolic syndrome and type II diabetes.

Other Important Tests to Measure:

• Oral Glucose Tolerance Test (OGTT): Measures glucose disposal after a glucose load. Blood samples are taken at 0, 30, 60, and 120 minutes after consuming 75g of glucose.
• Haemoglobin A1c Test (HbA1c): Estimates average glucose levels over 3 months. An HbA1c reading of 5.7% to 6.4% indicates pre-diabetes, while 6.5% or above indicates diabetes.
• Homeostasis Model Assessment of Insulin Resistance (HOMA-IR): Calculates insulin resistance using fasting glucose and insulin. The University of Oxford provides a calculator for this.
• Hyperinsulinemic-Euglycemic Clamp: Considered the gold standard for assessing insulin sensitivity, this involves a constant IV infusion of insulin to maintain blood glucose levels.
• Continuous Glucose Monitoring System (CGM): Provides continuous glucose readings and trend direction. Sensors are worn for up to 14 days and eliminate the need for frequent fingersticks.

Get your fasting insulin levels tested and interpreted by Dr. Marcus. Book a blood test here.

Yes, and?

Lifestyle changes specific to your fasting insulin levels such as diet modifications and stress management can improve insulin sensitivity, reduce diabetes risk, and prevent diabetes. 

Understanding the significance of fasting insulin levels opens the door to proactive health management strategies tailored to individual needs. By implementing simple dietary and lifestyle adjustments, backed by regular monitoring of insulin sensitivity, we empower ourselves to take charge of our metabolic health and pave the way towards a healthier and more vibrant future.

Sources:

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