Sweet Potato Glycemic Index
Medium GI · The honest verdict
A moderate blood-sugar rise
Glycemic index
44–94
reported range
Glycemic load
17
Medium GL
This food's glycemic index is 44–94, which is Medium GI.
Sweet potato is a nutrient powerhouse (especially vitamin A) but its GI varies widely. Boiled sweet potatoes have a medium GI and can be part of a diabetes-friendly meal in controlled portions. Baked or roasted sweet potatoes have a higher GI and should be eaten in smaller amounts. 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 potato GI ranges from 44 (boiled, skin on) to 94 (baked, orange variety) — one of the widest ranges of any common food.
One medium sweet potato (150 g, boiled) provides 1060 mcg vitamin A — over 100% of the daily value.
Boiling sweet potatoes with the skin on preserves cell structure and results in a significantly lower GI than baking or roasting.
Purple sweet potatoes have a lower GI (around 40–50) than orange varieties due to their anthocyanin content and different starch structure.
MedlinePlus (U.S. National Library of Medicine). Glycemic Index and Diabetes. NIH.
What's actually inside
Per 100 g, with your typical serving noted as 1 medium (150 g), boiled without skin. The carb family is what moves blood sugar — fiber is the number that softens the spike.
- Total carbs
- 31.2g
- Net carbs
- 26.1g
- total carbs minus fiber
- Fiber
- 5.1g
- slows the glucose rise
- Sugars
- 10.5g
- Protein
- 2.5g
- Calories
- 134kcal
Notable nutrients
- Vitamin A (RAE)1060 mcg
- Vitamin C22 mg
- Potassium542 mg
- Manganese0.6 mg
- Vitamin B60.3 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
Nutrient-dense but portion- and prep-dependent — a starchy root vegetable
Sweet potato is a nutrient powerhouse (especially vitamin A) but its GI varies widely. Boiled sweet potatoes have a medium GI and can be part of a diabetes-friendly meal in controlled portions. Baked or roasted sweet potatoes have a higher GI and should be eaten in smaller amounts. This is general nutrition information, not medical advice — people with diabetes should confirm serving guidance with their care team.
Portion guidance
A medium boiled sweet potato (150 g) provides about 26 g net carbs and a glycemic load of 17, which is in the medium GL range. A half-cup serving (about 100 g) reduces net carbs to ~17 g and GL to ~11, which is borderline low-medium. For better blood sugar control, stick to half a medium sweet potato per meal, boil rather than bake, and pair with protein and non-starchy vegetables. Avoid mashed or roasted sweet potatoes with added sugar or marshmallows.
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 whole with skin on
Lowers the spikeBoiling sweet potatoes with the skin on preserves cell structure and slows starch gelatinization, resulting in a lower GI (around 44–63) compared to other cooking methods.
Baking or roasting
Raises GIDry heat (baking/roasting) caramelizes sugars and fully gelatinizes starch, pushing GI higher (up to 82–94). The longer and hotter the bake, the higher the GI.
Mashing or pureeing
Raises GIMashing breaks down cell walls and makes starch more accessible to digestive enzymes, increasing GI compared to eating pieces.
Cooling after cooking (then eating cold or reheated)
Lowers the spikeCooling cooked sweet potato for several hours (e.g., in a salad) converts some starch to resistant starch, reducing GI. Reheating gently retains some of this benefit.
Pairing tip
Pair sweet potato with a lean protein source (chicken, fish, tofu, eggs) and a generous serving of non-starchy vegetables (broccoli, spinach, salad greens) to slow digestion and reduce the overall glycemic impact of the meal. Adding a source of healthy fat (olive oil, avocado, nuts) further blunts the blood sugar response. Avoid serving sweet potato alongside other high-carb foods like rice, bread, or sugary sauces.
Why GI numbers vary
Sweet potato GI data varies dramatically across sources because of real differences in variety (orange-fleshed sweet potatoes tend to have higher GI than white- or purple-fleshed varieties), cooking method, and even growing conditions. The University of Sydney GI Database reports values from 44 (boiled, skin on) to 94 (baked, orange variety). We report the honest range (44–94) and classify sweet potato as medium because the most common preparation (boiled or steamed, eaten in moderate portions) typically lands in the medium zone, though baked sweet potato can be high-GI. The wide range is genuine — not an artifact of poor data.
Not medical advice. This page is general nutrition information about Sweet Potato. 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 potato GI ranges from approximately 44 to 94 depending on variety and cooking method. Boiled sweet potatoes (especially with skin on) are medium-GI (44–63). Baked or roasted sweet potatoes, particularly orange-fleshed varieties, can reach high-GI values (82–94). Purple and white sweet potatoes tend to be lower-GI than orange varieties. Because the range is so wide, we report it honestly rather than picking a single misleading number.
Sweet potato can be part of a diabetes-friendly diet when prepared and portioned carefully. Boiled sweet potato in a half-cup serving has a moderate GI and provides fiber, vitamin A, and potassium. However, baked sweet potato has a much higher GI and should be eaten in smaller amounts. People with diabetes should monitor their individual response and discuss serving sizes with their care team — this is general nutrition information, not medical advice.
Boiled sweet potato typically has a lower GI (44–63) than boiled white potato (78–89), making it a better choice for blood sugar control when prepared similarly. However, baked sweet potato can approach the GI of baked white potato. The fiber content of sweet potato (about 5 g per medium potato) is higher than white potato (about 3 g), which helps slow glucose absorption. In practice, preparation method matters more than the type of potato.
Yes. Orange-fleshed sweet potatoes (the most common variety in the US) tend to have higher GI values than white- or purple-fleshed varieties. Purple sweet potatoes contain anthocyanins that may slow starch digestion, and some studies report their GI as low as 40–50. White sweet potatoes are also generally lower-GI than orange varieties. If blood sugar management is a priority, consider trying purple or white sweet potatoes.
Sweet potato is moderate in carbs — about 26 g net carbs per medium potato. On a moderate low-carb plan (50–100 g net carbs/day), half a medium sweet potato fits comfortably. On strict keto (under 20–30 g net carbs/day), even a half sweet potato uses a significant portion of the daily budget. Most keto followers limit sweet potato to small amounts or avoid it in favor of lower-carb vegetables.
Yes. Cooling cooked sweet potato for several hours (refrigerating overnight) converts some of its starch into resistant starch, which is not fully digested and therefore has less impact on blood sugar. This effect is well-documented for potatoes and sweet potatoes. A sweet potato salad made with cooled, boiled sweet potato, lemon juice, and olive oil is a lower-GI option than freshly baked sweet potato.
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Reviewed by
Curex Editorial TeamReviewed for accuracy
Last reviewed July 2026