Blood sugarEvidence-basedLesson 5 of 32

Glycemic index vs glycemic load

GI tells you how fast a carb raises blood sugar. Glycemic load tells you how much it actually matters.

4 min+20 XP

Index measures speed

Glycemic index ranks a food from 0–100 by how quickly its carbohydrate raises blood glucose compared to pure glucose. Under 55 is low, 56–69 medium, 70+ high.

Load measures reality

Watermelon has a high GI of 76, but a slice contains very little carbohydrate. Glycemic load = GI × grams of carbohydrate ÷ 100. That slice has a load of about 5 — negligible. A bagel has a load near 25.

What changes a food's impact

Fat, protein, fibre, acidity and even cooling cooked starches all slow glucose absorption. This is why Syndova estimates blood sugar impact from the whole meal, not from one number.

Key takeaways

GI = speed, glycemic load = speed × portion.
A load under 10 is low; over 20 is high.
Adding protein, fat or fibre lowers a meal's real impact.

Check your understanding

2 questions · answer to earn XP

1. How is glycemic load calculated?

2. Which of these lowers a meal's blood sugar impact?

Evidence & sources

This lesson reflects guidance from recognised health bodies and peer-reviewed research.

For education purposes only — not intended to diagnose, treat or replace medical advice.