When to test — timing blood glucose to catch spikes and crashes

Knowing when to check blood glucose is as important as checking itself. A few well-timed readings expose post-meal spikes and low points from activity or medications so you can adjust food, movement, or medicines with purpose.

Key times and why they matter

• On waking (fasting): shows overnight control and the “dawn” rise.

• Before meals: tells you whether glucose has returned to baseline and helps dose medication or plan portions.

• 1–2 hours after the start of a meal: captures the usual post-meal peak—test after the largest or most carb-heavy meal to find problem foods.

• Bedtime: helps detect overnight risk and decide evening snacks or med timing.

• Symptom-driven: test when you feel shakiness, sweating, confusion, or after unusual exercise to catch lows or unexpected drops.

Quick practical plan (start today)

• Simple 3-point plan for 7 days: fasting, 1–2 hours after your largest meal, and bedtime. Record meal, portion, meds, and activity with each reading.

• If strips are limited: prioritise fasting + 1–2 hours after the largest meal; add a bedtime or symptom check if hypoglycaemia is a concern.

One-line tips

• Start the post-meal clock at the first bite or sip.

• Short walk (10–20 minutes) after meals often reduces peaks—test before and after to see the benefit.

• Share weekly patterns (not single numbers) with your clinician for safe, targeted changes.