Making Sense of Your Continuous Glucose Monitor
Reading CGM data correctly is crucial for managing insulin resistance effectively. Here are the key principles that matter most.
1. Focus on Time in Range, Not Individual Spikes
Aim for 70% of your readings between 70-140 mg/dL. This metric is more important than avoiding every single spike, which is nearly impossible and unnecessary.
2. Understand Your Dawn Phenomenon
That early morning blood sugar rise is a normal cortisol response. Most people see a 10-30 point increase upon waking, which is completely physiological.
3. Post-Meal Spikes Under 180 Are Acceptable
What matters is that glucose returns to baseline within 2-3 hours. Brief spikes after eating are normal if your overall pattern is good.
4. Your Average Glucose Matters More Than Peaks
A stable 120 mg/dL average with occasional spikes to 160 is better than a 100 average with frequent drops to 60. Consistency beats perfection.
5. Context Is Everything
Stress, poor sleep, illness, menstrual cycles, and medications can all cause readings that have nothing to do with food. Do not make drastic diet changes based on one bad day.
Red Flags to Watch For
Seek medical attention if you see frequent readings above 200, time below 70 exceeding 4%, or persistent elevation without clear cause.
Making Practical Changes
Use your CGM data to identify your personal trigger foods and optimal meal timing. Small, consistent changes based on patterns will yield better results than dramatic restrictions based on single readings.
