Corn Glycemic Index
Low GI · The honest verdict
Gentle on blood sugar
Glycemic index
52–60
reported range
Glycemic load
14
Medium GL
This food's glycemic index is 52–60, which is Low GI.
Corn sits in the low-to-medium GI range, with a glycemic load that becomes moderate in typical servings. It has more carbs than non-starchy vegetables but provides fiber, B vitamins, and antioxidants like lutein. Portion size and preparation matter — eating corn on the cob with protein and vegetables is better than processed corn products. This is general nutrition information, not medical advice — people with diabetes should confirm serving guidance with 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
Sweet corn GI is estimated in the 52–60 range — a starchy grain-vegetable with low-to-medium blood sugar impact.
One half-cup of cooked sweet corn provides 2.3 g fiber and 2.8 g protein — more than most non-starchy vegetables.
Glycemic load of 11–19 is classified as medium — a half-cup of corn sits at the low end of this range.
What's actually inside
Per 100 g, with your typical serving noted as 1/2 cup (82 g), cooked sweet corn kernels. The carb family is what moves blood sugar — fiber is the number that softens the spike.
- Total carbs
- 17.1g
- Net carbs
- 14.8g
- total carbs minus fiber
- Fiber
- 2.3g
- slows the glucose rise
- Sugars
- 3.3g
- Protein
- 2.8g
- Calories
- 77kcal
Notable nutrients
- Vitamin C5.5 mg
- Potassium196 mg
- Magnesium26 mg
- Thiamin (Vitamin B1)0.1 mg
- Folate35 mcg
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
Manageable with portion control — a starchy grain-vegetable
Corn sits in the low-to-medium GI range, with a glycemic load that becomes moderate in typical servings. It has more carbs than non-starchy vegetables but provides fiber, B vitamins, and antioxidants like lutein. Portion size and preparation matter — eating corn on the cob with protein and vegetables is better than processed corn products. This is general nutrition information, not medical advice — people with diabetes should confirm serving guidance with their care team.
Portion guidance
A half-cup of cooked sweet corn kernels (about 82 g) contains roughly 15 g net carbs and a glycemic load of around 14, which is moderate. One medium ear of corn (about 90 g kernels) is similar. Sticking to one ear or half a cup per meal, and pairing with protein (chicken, beans) and non-starchy vegetables, keeps the overall glycemic impact moderate. Avoid oversized portions or processed corn products like corn syrup and corn chips.
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.
Boiling or steaming whole ears
Little effectBoiling or steaming sweet corn on the cob preserves the kernel structure and keeps the GI in the low-to-medium range. This is the most common preparation and the one used in most GI studies.
Grilling or roasting
Raises GIGrilling or roasting corn can caramelize natural sugars and reduce moisture, slightly concentrating carbs and potentially raising the GI compared to boiling.
Processing into cornmeal or popcorn
Raises GIGround corn products (cornmeal, polenta, grits) have a higher GI than whole-kernel corn because grinding breaks down starch structure. Popcorn has a moderate GI but a low glycemic load per volume due to its air content.
Cooling after cooking
Lowers the spikeCooling cooked corn converts some starch to resistant starch, which is digested more slowly. Reheating gently retains part of this benefit, modestly lowering the glycemic response compared to freshly cooked corn.
Pairing tip
Serve corn alongside grilled chicken, fish, or beans to add protein that slows digestion. A side of leafy greens or bell peppers adds fiber without meaningful carbs. Avoid butter-heavy preparations or pairing corn with other high-carb foods like rice, potatoes, or bread in the same meal. A squeeze of lime or vinegar can help moderate the glycemic response.
Why GI numbers vary
Corn GI data varies because different types of corn have different starch compositions. Sweet corn (the type eaten as a vegetable) has a GI typically reported between 52 and 60, while field corn (used for cornmeal and animal feed) has a higher GI. Preparation also matters: whole-kernel corn has a lower GI than ground corn products. We report the honest range (52–60) for sweet corn and classify it as low because the lower end of the range is most representative of how it's commonly eaten.
Not medical advice. This page is general nutrition information about Corn. 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
Sweet corn has a glycemic index ranging from about 52 to 60, placing it in the low-to-medium GI zone. The exact value depends on the variety (sweet corn vs. field corn) and cooking method. Boiled or steamed sweet corn on the cob tends toward the lower end of this range. Because sources vary, we report a range rather than a single value. In practical terms, treat corn as a moderate-GI starchy vegetable.
Corn can fit into a diabetes-friendly diet with portion control. A half-cup serving has a glycemic load of about 14, which is moderate. Corn provides fiber, B vitamins, and antioxidants like lutein. However, it is a starchy food with more carbs than non-starchy vegetables like broccoli or spinach, so portion size matters. People with diabetes should discuss serving sizes with their care team — this is general nutrition information.
Corn has a lower GI (52–60) than white potatoes (typically 70–85 for baked or mashed), making it a better choice for blood sugar management. Corn also has more fiber per serving than potatoes. However, both are starchy foods that require portion control. Sweet potatoes have a GI similar to corn (around 50–60), making them a comparable alternative.
Corn at about 15 g net carbs per half-cup is moderate for low-carb diets. On a moderate low-carb plan (50–100 g net carbs/day), half a cup fits easily. On strict keto (under 20–30 g/day), even a half-cup uses a significant portion of the daily budget. Most keto followers limit corn or use very small portions as a garnish. Processed corn products like tortilla chips are much harder to fit.
Yes. Sweet corn (the yellow or white corn eaten as a vegetable) has a lower GI than field corn (used for cornmeal, grits, and animal feed). Baby corn, which is harvested early, has even fewer carbs and a lower GI. Processed corn products like corn syrup, corn chips, and cornflakes have much higher GIs and should be limited by anyone managing blood sugar.
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Reviewed by
Curex Editorial TeamReviewed for accuracy
Last reviewed July 2026