Science

The glycemic index, explained

You don't need to memorise GI tables — here's what actually matters and why.

What GI and GL actually measure

The glycemic index (GI) ranks how quickly a carbohydrate-containing food raises blood sugar compared to pure glucose. Glycemic load (GL) adjusts for typical portion size, since GI alone can be misleading for foods rarely eaten in large amounts (watermelon has a high GI but a modest GL per typical serving).

Why this connects to inflammation

Frequent high-GI/GL meals produce sharper blood sugar and insulin spikes, which — as covered in our sugar deep dive — are associated with more inflammatory signalling over time compared to more gradual, stable blood sugar patterns.

Practical, low-effort ways to lower a meal's glycemic load

Pairing carbohydrates with protein, fat or fibre; choosing whole over refined grains; and not needing to eliminate any food outright — swapping white rice for a fibre-rich alternative, or simply adding vegetables and protein alongside a carb-heavy meal, meaningfully blunts the spike without requiring elimination.

You don't need to memorise GI tables. "Pair carbs with protein, fat or fibre" captures most of the practical benefit.

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