Insulin Resistance and Fasting

Insulin – What it Does

Insulin is all about getting the glucose (or sugar that your body breaks down from the foods you eat) into your cells for fuel.

How Your Body Works

  • First you eat some food.
  • Your body sends a signal to your pancreas to produce insulin.
  • Your body breaks that food down into glucose.
  • Then the glucose gets absorbed into your blood stream for transport to your cells.
  • The insulin is what opens the way for the glucose to be received by your cells.  Then cells use this for energy.
  • Extra glucose that isn’t needed by your cells at this time is stored as fat to be used later.

When everything is working correctly food produces glucose, insulin is released, the energy is used by your cells and no body fat is stored.

Once your body uses all the glucose in your system it will move on to use the glycogen (the stored glucose).  That is great you are now burning fat.

Insulin Resistance Symptoms

  • Fatigue
  • Extra weight in the mid-section
  • Elevated fasting blood sugar
  • PCOS
  • Fatty liver disease
  • Sugar or Carb Cravings
  • High blood pressure
  • Fluid retention
  • Skin Problems / dark patches / acne

Blood Tests:

Hemoglobin A1c –

Below 5.7% Normal
5.7% to 6.4% Prediabetes
Over 6.5%– Diabetes

Fasting Glucose – Overnight

<100 mg/dL – Normal
100 to 125 mg/dL – Prediabetes
>126 mg/dL – Diabetes

Intermittent Fasting

Elevated insulin is the most relevant factor in developing insulin resistance. If you are insulin resistant then your insulin levels are elevated all the time.    The Theory is that fasting helps to lower your insulin levels and this breaks the persistent high; helping your body to reset itself.  It resets your insulin sensitivity.

  • Avoiding food for a time and then eating normally other times.
  • Fast from 12-20 hours per day
  • Eat all the food you need in a day in a short window of time.
  • This isn’t body starvation.  Prolonged fasting can also make you insulin resistant.

The Latest Research

New research from the University of Alabama demonstrates that eating in an 8 hour window and then not eating the rest of the 24 hours lowered insulin levels, improved insulin sensitivity and lowered blood pressure.

The Subjects:  Obese Men with Prediabetes placed into 2 groups

Group 1:  “Early Time-Restricted Feeding” all meals were eaten in an eight-hour period from 7am to 3pm.

Group 2: All meals were eaten in a twelve-hour period from 7am to 7pm.

Conclusion:  Eating early in the day and extending the overnight fast benefited metabolism.

DO NOT TRY Intermittent Fasting:

  • If you are on diabetes medication
  • Have a history of anorexia or bulimia
  • Are pregnant or breastfeeding

For Your Best Health:

  • Avoid sugars and processed foods
  • Eat a diet high in fruits and vegetables and lean proteins
  • Don’t snack
  • Get some exercise
  • Consider simple intermittent fasting (7am to 3pm or 10am to 6pm)

Improving your body’s sensitivity to insulin can help curb hunger, stabilize weight and improve cardiovascular health and fasting may just be the way to do that.

What Does Fasting Do To Insulin?



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