What is a low glycemic index food?

A low GI food scores 55 or below on the glycemic index scale. These foods are digested more slowly, producing a gentler rise in blood glucose. Examples include lentils (GI 32), apples (GI 36), sweet potatoes (GI 44), and most berries (GI 25–53). Low GI foods are generally better for sustained energy and blood sugar management.

What is considered a high glycemic index?

Foods scoring 70 or above are classified as high GI. White bread (75), baked potato (85), cornflakes (81), and white rice (73) are common examples. High GI doesn't automatically mean unhealthy — watermelon scores 72 but is a whole, unprocessed fruit with very few calories. Context matters, which is why SpikeSaver shows GI alongside NOVA score and hidden sugars.

Is a glycemic index of 36 good?

Yes — 36 is classified as low GI, meaning the food releases glucose slowly and won't cause a sharp spike in blood sugar. For comparison, lentils score 32, apples score 36, and yoghurt scores 36. Foods in this range are generally considered good for blood sugar management.

What is a healthy glycemic index?

There's no single 'healthy' GI number — it depends on the food and your goals. As a general guide: low GI (55 or below) is preferred for sustained energy and blood sugar control. But GI alone doesn't determine whether a food is healthy. A chocolate bar might score lower GI than watermelon due to its fat content, but that doesn't make it a better choice. SpikeSaver combines GI with NOVA classification and hidden sugar count to give you the full picture.

How is the glycemic index measured?

GI is measured by feeding a group of volunteers (usually 10+) a portion of food containing 50g of digestible carbohydrate, then measuring their blood glucose response over 2 hours. This is compared against the response from 50g of pure glucose (which scores 100). The result is expressed as a percentage. Testing is done under controlled conditions by accredited laboratories.

What's the difference between glycemic index and glycemic load?

Glycemic index (GI) measures how quickly a food raises blood sugar, but ignores portion size. Glycemic load (GL) factors in how much carbohydrate a typical serving contains. GL = (GI × carbs per serving) ÷ 100. A GL of 10 or below is low, 11–19 is medium, and 20+ is high. Watermelon has a high GI (72) but low GL (4) because you'd need to eat a lot to get 50g of carbs from it.

Does cooking method affect glycemic index?

Yes — significantly. Al dente pasta has a lower GI than overcooked pasta. Boiled potatoes score lower than baked or mashed. Cooling starchy foods (like rice or potatoes) after cooking creates resistant starch, which lowers the GI. Green bananas have a lower GI than ripe ones because the starch hasn't yet converted to sugar.

Can low GI foods still be ultra-processed?

Absolutely. GI only measures glucose response — it says nothing about processing level, additives, or hidden ingredients. Nutella scores a medium GI of 55, but it's NOVA 4 (ultra-processed) with 5+ UPF markers. That's why SpikeSaver shows GI alongside NOVA classification and hidden sugar count — one number never tells the whole story.

What is the Glycemic Index?

The glycemic index (GI) ranks foods from 0 to 100 based on how quickly they raise blood glucose after eating. Low GI foods (55 or below) release energy slowly and produce a gentle glucose rise. High GI foods (70 or above) cause a rapid spike. SpikeSaver layers GI alongside NOVA classification and hidden sugar counts so you see the full picture — not just how fast a food hits your blood sugar, but how processed it is and what hidden ingredients it contains.

The GI scale

Low GI0–55

Slow digestion, gentle glucose rise. These foods release energy gradually and help maintain steady blood sugar levels.

lentils (32), apple (36), sweet potato (44), oats (55), quinoa (53), most berries (25–53)

Medium GI56–69

Moderate glucose response. These foods raise blood sugar at a moderate rate.

banana (51–62), Weetabix (69), porridge (55–66), popcorn (65), beer (66), Yorkshire pudding (67)

High GI70–100

Rapid glucose spike. These foods are digested and absorbed quickly, causing a fast rise in blood sugar.

white bread (75), baked potato (85), white rice (73), cornflakes (81), French fries (75), watermelon (72)

Why GI alone isn't enough

GI tells you how fast a food raises blood sugar — but it doesn't tell you the whole story. A food can be low GI and still ultra-processed (Nutella scores 55), or high GI and completely unprocessed (watermelon scores 72). That's why SpikeSaver shows GI alongside NOVA classification and hidden sugar detection. The three signals together tell you what a food actually does to your body — not just one dimension of it.

GI vs glycemic load (GL)

The glycemic index measures how quickly a food raises blood sugar, but it doesn't account for portion size. That's where glycemic load (GL) comes in. GL = (GI × carbs per serving) ÷ 100. A food like watermelon has a high GI (72) but a low GL (4) because a typical serving contains very few carbohydrates. Conversely, white rice has a high GI (73) AND a high GL (29) because a typical serving is carb-heavy. SpikeSaver shows both GI and glucose impact rating to capture this nuance.

Glycemic index of 40 common foods

Sorted by GI score (highest first). Click any food for full nutrition data.

Food	GI	Rating
Baked Potato	89	High
Mashed Potatoes	85	High
Coco Pops	77	High
Fries / Chips	75	High
White Bread	75	High
Nachos / Tortilla Chips	74	High
Ritz Crackers	74	High
Rice	73	High
Watermelon	72	High
Naan Bread	71	High
Porridge	69	Medium
Weetabix	69	Medium
Yorkshire Pudding	67	Medium
Cantaloupe	65	Medium
Jelly	65	Medium
Sweet Potato	63	Medium
Dates	62	Medium
Pizza	60	Medium
Honey	57	Medium
Nutella	55	Low
Popcorn	55	Low
Quinoa	53	Low
Banana	51	Low
Dark Chocolate	45	Low
Beer	40	Low
Strawberries	40	Low
Pear	38	Low
Apple	36	Low
Black Beans	30	Low
Lentils	29	Low
Whole Milk	27	Low
Edamame	18	Low
Avocado	15	Low
Lettuce	15	Low
Peanuts	14	Low
Yogurt	14	Low
Broccoli	10	Low
Chicken Breast	0	Low
Eggs	0	Low
Salmon	0	Low

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