Fruit and diabetes: the glycaemic index and load of 16 common fruits

The short answer

Almost every whole fruit is a reasonable choice if you have diabetes. Most fruits have a low glycaemic index, and in a normal serving most have a low glycaemic load, which is the better guide to how much a portion will raise your blood sugar. Of the 16 common fruits in this guide, grapefruit, strawberries, cherries, peaches, apples and oranges have the lowest load; bananas, grapes and raisins the highest, though still only medium.

That does not make any fruit off-limits, or any one a cure. How much you eat, what you eat it with and whether you eat it whole matter more than which fruit you choose. This guide ranks the fruits, explains what the numbers mean and sets out what the research says about fruit and diabetes.

It is general information, not medical advice. If you take insulin or medicines that can cause low blood sugar, your diabetes team can help you fit fruit into your carbohydrate plan.

GI and GL: what the two numbers mean

The glycaemic index (GI) ranks carbohydrate foods by how quickly they raise blood sugar compared with pure glucose, which scores 100. A GI of 55 or under is low, 56 to 69 medium and 70 or over high. It compares foods gram of carbohydrate for gram of carbohydrate, so it says nothing about how much carbohydrate a normal portion contains.

The glycaemic load (GL) fixes that. It multiplies the GI by the carbohydrate in a serving (not counting fibre) and divides by 100. A GL of 10 or under is low, 11 to 19 medium and 20 or over high. Because it accounts for portion size, it is the better guide to what a serving will actually do to your blood sugar.

Watermelon shows why the difference matters. Its GI is high, at about 76, but it is mostly water: 120 g holds under 9 g of carbohydrate, so its glycaemic load is only about 7 — low.

16 common fruits, ranked

Fruit	Serving	Glycaemic index	Net carbs per serving	Glycaemic load per serving
Grapefruit	120 g	25 (low)	11 g	3 (low)
Strawberries	120 g	40 (low)	7 g	3 (low)
Cherries	120 g	22 (low)	17 g	4 (low)
Peach	120 g	42 (low)	10 g	4 (low)
Prunes	30 g	29 (low)	17 g	5 (low)
Apple	120 g	36 (low)	14 g	5 (low)
Orange	120 g	43 (low)	11 g	5 (low)
Pear	120 g	38 (low)	15 g	6 (low)
Kiwi	120 g	About 50 (low)	14 g	7 (low)
Watermelon	120 g	76 (high)	9 g	7 (low)
Mango	120 g	51 (low)	16 g	8 (low)
Blueberries	120 g	53 (low)	15 g	8 (low)
Pineapple	120 g	59 (medium)	14 g	8 (low)
Banana	120 g	51 (low)	24 g	12 (medium)
Grapes	120 g	59 (medium)	21 g	12 (medium)
Raisins	30 g	64 (medium)	23 g	14 (medium)

The glycaemic index figures are published averages drawn from the international GI tables, as summarised in Harvard Health’s table. Net carbohydrate and glycaemic load are our calculations from USDA FoodData Central carbohydrate and fibre figures. Fresh fruit is compared at 120 g — the standard serving the GI tables use, and roughly one medium apple, a large handful of grapes or a cup of berries. Dried fruit is compared at 30 g, one portion in NHS 5 A Day guidance, because 120 g of raisins is far more than anyone eats at once. Real values move with variety and ripeness: a riper banana has a higher GI than a greener one, for example.

What the research says about fruit and diabetes

Cutting back on fruit does not help

The most direct evidence is a 2013 randomised trial in 63 adults with newly diagnosed type 2 diabetes. Half were advised to eat at least two pieces of fruit a day, half to eat no more than two. After 12 weeks, HbA1c — the main measure of long-term blood sugar — had fallen by the same amount in both groups, and weight and waist size did not differ. The researchers concluded that fruit should not be restricted in type 2 diabetes.

Whole fruit is linked with lower risk; juice with higher

In a 2013 analysis of three large US cohorts — more than 187,000 people followed for decades — eating more whole fruit, especially blueberries, grapes and raisins, and apples and pears, was linked with a lower risk of developing type 2 diabetes. Drinking more fruit juice was linked with a higher risk. In a study of half a million adults in China, people with diabetes who ate fresh fruit more often had lower rates of death and of complications affecting the heart and blood vessels. These are observational studies, so they show links rather than proof, but they point the same way.

Fruit before a meal may soften the rise

Small trials have found that eating an apple before a rice meal lowered the blood-sugar peak afterwards by a third to a half, compared with the rice meal alone. They were in people without diabetes and have not been repeated for most fruits, so treat this as a strategy to test with your own meter or sensor. We cover them in apples vs pears for diabetes.

Guidelines agree

Both the American Diabetes Association and Diabetes UK encourage fruit as part of a healthy diet with diabetes, favour whole fruit over juice and suggest spreading it through the day.

The best picks, and the ones to portion

Lowest load: citrus, berries, stone fruit, apples and pears

Grapefruit and strawberries are the lowest, at a glycaemic load of about 3 per 120 g. Cherries have the lowest glycaemic index here, at 22, and peaches sit at about 4. Oranges, apples and pears all come in around 5 to 6, and add useful fibre — pears the most. These are easy everyday choices. Grapefruit can interact with some medicines, including certain statins and blood-pressure drugs, so check with a pharmacist if you take any — our grapefruit article lists them.

Still low: kiwi, blueberries, mango, pineapple and watermelon

All have a low load in a 120 g serving. Keep an eye on portions of mango and pineapple, which are easy to eat in larger amounts, and watermelon, whose high GI means a big slice raises blood sugar faster than its low load suggests.

Medium: bananas and grapes

A 120 g serving — roughly one medium banana, or a large handful of grapes — has a medium glycaemic load of about 12. They are still fine to eat: choose a smaller banana, or one that is less ripe, and count out a portion of grapes rather than eating from the bunch.

Dried fruit: prunes low, raisins medium

Drying removes water and concentrates the sugar, so dried fruit is compared at a 30 g portion — about a heaped tablespoon. Prunes come out low, at a glycaemic load of about 5, with a low GI of 29 and plenty of fibre. Raisins are medium, at about 14, with a GI of 64. A few prunes are a reasonable choice; raisins are best kept to small amounts, and neither should be eaten by the handful. See are raisins good for diabetes? for portions and the trials.

How to eat fruit with diabetes

• Count it as carbohydrate. A small piece of fruit, or about half a cup of chopped fruit, is roughly 15 g of carbohydrate. If you count carbohydrates for insulin, weigh a few portions to learn your usual sizes.
• Eat it whole. Keep the skin on where you can; it holds much of the fibre that slows the sugar down.
• Pair it with protein or fat. Fruit with plain yoghurt, a handful of nuts or some cheese gives a gentler rise and keeps you fuller.
• Spread it through the day. One portion at a time, rather than several at once.
• Limit juice and smoothies. They lose much of the fibre, raise blood sugar faster and their sugars count as free sugars. Blending can also make it easy to consume several portions of fruit in one drink.
• Go easy on dried fruit. Drying concentrates the sugar: 30 g of raisins carries about as much carbohydrate as 120 g of grapes. Keep portions to about a tablespoon, and prefer prunes to raisins.
• Choose tinned fruit in juice or water, not syrup, and drain it.
• Check your own response. People vary. Your meter or sensor readings two hours after eating are the best guide to which fruits and portions suit you.

Who should take extra care

• People on insulin or sulfonylureas. Count fruit in your carbohydrate plan, and ask your diabetes team if you are unsure how.
• People treating a low. Whole fruit is too slow and too variable to treat hypoglycaemia. Use fast-acting glucose as your team advises.
• People with kidney disease. Bananas, oranges and kiwi are relatively high in potassium. If you have been told to limit potassium, check which fruits and portions suit you with your dietitian.
• People with IBS. Apples, pears, mango and watermelon are high in FODMAPs. Strawberries, oranges, kiwi and firm bananas are usually better tolerated.

Read more

• Apples vs pears: which is better for diabetes? — a side-by-side comparison, and the evidence for each.
• What happens if you eat two apples a day for a week?
• What happens if you eat two pears a day for a week?