Lettuce Glycemic Index
Low GI · The honest verdict
Gentle on blood sugar
Glycemic index
15
per source
Glycemic load
1
Low GL
This food's glycemic index is 15, which is Low GI.
Lettuce is essentially a non-issue for blood sugar: it is over 95% water, has under 2 grams of net carbs per large serving, and a very low glycemic index. Even very large portions are unlikely to move glucose in a meaningful way. This is general nutrition information, not medical advice; people with diabetes should consult their care team.
GI numbers vary by source, ripeness, and how a food is prepared. This is general nutrition information — not medical advice. If you manage diabetes, confirm specifics with your care team.
Key facts
Lettuce is over 95% water — a full 2-cup serving contains under 2 grams of net carbohydrate.
Foods scoring 55 or below on the glycemic index are classified as low-GI; lettuce, at around 15, is among the lowest.
Glycemic load — which factors in carbs per serving — is near zero for lettuce, making it a practical blood-sugar non-event at any normal portion size.
What's actually inside
Per 100 g, with your typical serving noted as 2 cups shredded (94 g), raw. The carb family is what moves blood sugar — fiber is the number that softens the spike.
Total carbs
2.2g
Net carbs
1.3g
total carbs minus fiber
Fiber
0.9g
slows the glucose rise
- Sugars
- 1g
- Protein
- 0.9g
- Calories
- 12kcal
Notable nutrients
- Vitamin K62 mcg
- Vitamin A2470 IU
- Folate29 mcg
- Vitamin C5 mg
Is it a smart choice for blood sugar?
GI is only half the story — portion (glycemic load) and what you eat it with decide the real-world effect. Here's the honest read.
The verdict
One of the most blood-sugar-neutral foods available
Lettuce is essentially a non-issue for blood sugar: it is over 95% water, has under 2 grams of net carbs per large serving, and a very low glycemic index. Even very large portions are unlikely to move glucose in a meaningful way. This is general nutrition information, not medical advice; people with diabetes should consult their care team.
Portion guidance
Lettuce requires essentially no portioning from a blood-sugar standpoint. A large salad bowl (3–4 cups) still contributes only 2–3 grams of net carbs. The dressings and toppings you add will have a far greater glycemic impact than the lettuce itself.
This is general nutrition information, not personal medical advice. Blood sugar responses are individual — if you have diabetes or prediabetes, your care team can tell you how this fits your plan.
How to keep the spike small
The same food can land differently depending on how it's cooked and what it's eaten with. Use these levers to your advantage.
Eating raw
Lowers the spikeRaw lettuce retains full water content and cell structure, producing an already negligible glucose response.
High-sugar dressings or croutons
Raises GISweetened dressings, croutons, or candied toppings can add significant fast-digesting carbs to an otherwise blood-sugar-neutral salad. The lettuce is not the culprit — the toppings are.
Adding protein and healthy fat
Lowers the spikeGrilled chicken, eggs, nuts, or avocado in the salad slow digestion of the whole meal, making the glucose response of any carbs in the bowl even more gradual.
Pairing tip
Lettuce is already a glycemic non-event, so the pairing strategy is really about keeping dressings lower in added sugar (olive oil and lemon are ideal) and adding protein like grilled chicken, tuna, or eggs to make the whole meal more satiating and blood-sugar stable.
Why GI numbers vary
Formal GI studies on plain lettuce are rare because the carbohydrate content is so low that a standard GI test dose (50 g available carbs) would require consuming an impractical amount. The commonly cited value of around 15 is an estimate consistent with other leafy greens and the food's nearly carb-free composition. The key practical point is that lettuce contains almost no digestible carbohydrate, making GI largely theoretical in this case.
Not medical advice. This page is general nutrition information about Lettuce. It isn't a diagnosis or a treatment plan. If you have diabetes, prediabetes, or another condition affecting blood sugar, confirm any dietary decisions with your doctor or care team.
❓Frequently Asked Questions
Lettuce has an estimated glycemic index of around 15, well within the low-GI range (55 and below). In practice, the GI is almost theoretical because lettuce contains so few digestible carbohydrates — a large serving provides only about 1–2 grams of net carbs, yielding a glycemic load close to zero. Different varieties (romaine, iceberg, butterhead) are all similarly low.
Yes — lettuce is one of the most blood-sugar-friendly foods available. It has virtually no digestible carbohydrate, a very low GI, and a negligible glycemic load. Most diabetes nutrition guidance treats leafy greens as unrestricted vegetables. Individual responses can vary, and what you dress the salad with matters far more than the lettuce itself — confirm any dietary changes with your care team.
Essentially no. A large salad bowl of lettuce contains only 1–2 grams of net carbs — too small an amount to cause a meaningful blood-sugar rise in most people. Sugary dressings, croutons, or high-carb toppings are the real variables to watch, not the lettuce leaves themselves.
Both are extremely low-GI leafy greens — the difference in practice is negligible from a glycemic standpoint. Romaine has slightly more fiber and nutrients like vitamin A and folate per gram, but iceberg and butterhead lettuce are similarly low in carbs and will not meaningfully raise blood sugar either.
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Reviewed by
Curex Editorial TeamReviewed for accuracy
Last reviewed July 2026