Of all the medical tests out there, fasting insulin is one of the most useful for assessing your true metabolic health. Unlike mere weight or BMI readings, this simple blood test provides a window into what’s going on inside your cells and how well your metabolism is functioning.
Here’s a closer look at fasting insulin, what the readings mean, and why it deserves your attention:
What is Fasting Insulin?
A fasting insulin test measures the level of insulin in your bloodstream after you haven’t eaten for at least 8 hours. It provides an indication of how much insulin your body is producing overall.
Higher fasting insulin levels suggest that the body is releasing more insulin in response to elevated blood sugars. This typically indicates insulin resistance or pre-diabetes.
Reference Ranges
Fasting insulin is measured in μIU/mL (microinternational units per milliliter). The reference ranges are:
- Normal: Less than 5 μIU/mL
- Pre-diabetes: 5 to 10 μIU/mL
- Diabetes: Greater than 10 μIU/mL
So aiming for a reading under 5 is optimal, while over 10 suggests insulin resistance and metabolic problems.
Why It Matters More Than Weight
Many doctors rely on weight, BMI or blood glucose alone to assess metabolic issues. However, fasting insulin provides a more comprehensive understanding because it reflects insulin sensitivity at the cellular level.
A person can have normal BMI and blood sugar but high insulin, indicating “TOFI” – thin on the outside, fat on the inside. This means obesity-related issues lurking under the surface.
Conversely, one can be overweight but maintain low fasting insulin. In this case, the extra weight may not be driving disease, at least not yet.
That’s why fasting insulin reveals metabolic health insights beyond just the scale.
Diet and Lifestyle Impact
The good news is fasting insulin responds readily to diet and lifestyle interventions.
When you significantly reduce added sugars and processed carbs, your insulin demands decrease and fasting insulin trends lower over weeks and months.
Exercise, sleep, stress management and other lifestyle factors also play a role in stabilizing insulin.
These changes may not always reduce body weight much, but can dramatically improve insulin sensitivity and other metabolic markers.
Ask For This Test
Because of its value in assessing metabolism, insulin resistance and diabetes risk, request a fasting insulin test from your doctor. Get levels below 5 through nutrition and lifestyle measures.
Tracking this number over time provides invaluable feedback on how diet and other interventions are impacting your metabolic health on a cellular level.
So be sure to add fasting insulin to your list of key blood tests. Keeping levels in a healthy range helps safeguard you against obesity, diabetes, heart disease and other ills over the long-term.
