Kiwi fruit is a popular and nutritious fruit that is rich in vitamin C, vitamin E, potassium, and fiber. However, some people with diabetes or prediabetes wonder if the natural sugars in kiwi fruit will cause spikes in their blood sugar levels. This article will examine the evidence on kiwi fruit and blood sugar control.
Does Kiwi Fruit Contain Sugar?
Yes, kiwi fruit does contain natural sugars. One medium kiwi (around 68 grams) contains:
- 15 grams of carbohydrates
- 8 grams of sugar
The sugar in kiwi fruit includes glucose, fructose, and sucrose. Since kiwi is a fruit, it contains simple sugars that can raise blood sugar levels. But the fiber, fat, protein, and water content help attenuate the blood sugar response compared to consuming sucrose (table sugar) alone.
Kiwi Fruit Glycemic Index
The glycemic index (GI) is a measure of how quickly a food raises blood sugar. Foods are ranked on a scale of 0 to 100.
Pure glucose is used as the reference food with a GI of 100. Foods with a high GI (70 or greater) raise blood sugar quickly. Low GI foods (55 or less) raise blood sugar slowly.
Kiwi fruit has a low to moderate glycemic index of 52. This means it shouldn’t cause major spikes in blood sugar compared to high GI foods like rice (GI 79), bread (GI 71), or potatoes (GI 78).
However, ripeness impacts the GI somewhat. Ripe kiwi fruit has a GI of 56 while unripe kiwi fruit has a GI of 41.
Kiwi Fruit Glycemic Load
Glycemic load accounts for the total carbohydrates in a serving of food. It’s calculated by multiplying the GI by the grams of carbohydrate per serving.
Glycemic load gives a more realistic idea of the blood sugar impact of real-world portion sizes. For example, watermelon has a high GI but a low glycemic load per serving due to its high water and low carb content.
A glycemic load under 10 is considered low while a load over 20 is high. The glycemic load of one kiwi fruit is 6, which is considered a low glycemic load food.
This means that despite having sugar, kiwi is unlikely to spike blood sugar dramatically due to the fiber and water content diluting the sugar load into the bloodstream.
Fiber Content
One of the reasons that kiwi fruit has a low glycemic impact is its fiber content.
A medium kiwi contains 2.1 grams of fiber. The skin alone contains 1 gram of fiber, so eating the skin boosts the fiber intake.
Fiber slows digestion and the absorption of sugar into the bloodstream after a meal. Soluble fiber can also reduce spikes in blood sugar levels.
This effect may be enhanced by consuming kiwi fruit with the skin, as the skin is particularly high in soluble fiber.
Can Kiwi Fruit Help Lower Blood Sugar Levels?
Some research indicates that kiwi fruit may even lower blood sugar levels.
In one study of people with impaired glucose tolerance, eating two kiwifruits per day for 12 weeks lowered HbA1c levels compared to the control group. HbA1c provides an average blood sugar level over the past 2-3 months.
Another study in people with type 2 diabetes found that consuming two gold kiwifruits per day for 12 weeks significantly reduced fasting blood sugar levels, total cholesterol, and LDL cholesterol compared to eating an apple a day.
The researchers noted fresh kiwi fruit may be more effective for glycemic control than processed, dried kiwi. This is likely due to the higher fiber content of fresh kiwifruit.
Potential mechanisms:
- The fiber delays gastric emptying and slows digestion and sugar absorption.
- Kiwi is high in vitamin C which improves insulin sensitivity.
- Antioxidants in kiwi reduce oxidative stress and inflammation linked to insulin resistance.
- Kiwi contains actinidin, an enzyme that helps digest protein. Better protein digestion may improve the insulin response.
Overall the research indicates kiwi fruit does not spike blood sugar levels dramatically due to the fiber content. Kiwi may even lower blood sugar levels and improve glycemic control in those with impaired glucose regulation.
Tips for Adding Kiwi to a Diabetes-Friendly Diet
Here are some ways to incorporate kiwi into your diet if you have diabetes:
- Enjoy sliced kiwi fruit topped with plain Greek yogurt for breakfast.
- Add diced kiwi to your overnight oats or chia seed pudding.
- Mix kiwi into green salads or fruit salads.
- Blend kiwi into smoothies along with spinach and avocado.
- Mix diced kiwi into plain skyr or quark cheese as a dessert.
- Layer sliced kiwi over pancakes or waffles instead of syrup.
- Top Greek yogurt with kiwi slices, chia seeds, and cinnamon.
- Add kiwi to kebabs alternating with shrimp, chicken, or turkey.
- Blend kiwi into homemade fruit popsicles sweetened with stevia.
- Slice kiwi over wholegrain toast topped with ricotta cheese.
When buying kiwi:
- Choose firm kiwi that gives slightly when pressed.
- Avoid very soft or bruised kiwi.
- Let firm kiwi ripen at room temperature for a few days until soft.
- Choose low-sugar varieties like golden kiwi which is less tart than green kiwi.
- Always eat the skin for extra fiber.
Precautions
Kiwi fruit is safe for most people with diabetes. However, those with very poorly controlled blood sugar levels should be cautious with portion sizes of all fruits. Speak to your doctor about your individual fruit intake.
Some medications like beta-blockers may raise potassium levels. Large intakes of high-potassium foods like kiwi may further increase potassium levels. Those on potassium-altering medications should speak to their doctor about potassium-rich fruits.
Allergies to kiwi fruit are fairly common. Symptoms may include itchy mouth, swelling of the throat, and digestive upset. Those with kiwi allergies should avoid this fruit.
The Bottom Line
Kiwi fruit has a low to moderate effect on blood sugar levels. The natural sugar and carbohydrates in kiwi are diluted by its high water and fiber content. Kiwi fruit may even lower HbA1c and improve glycemic control compared to other fruits. Still, portion size matters for any fruit if you have diabetes. Enjoy kiwi fruit in moderation as part of a healthy diabetes diet. Pair it with protein, healthy fats, and fiber for the best blood sugar control.
Frequently Asked Questions
Is kiwi good for diabetics?
Yes, kiwi can be a good fruit choice for many diabetics due to its low glycemic index and high fiber content. Kiwi does contain natural sugars, but its glycemic load is low. Enjoy kiwi in moderation.
What fruits should diabetics avoid?
Fruits with a very high glycemic index that diabetics should avoid in big portions include dried fruits like raisins, dates and figs, watermelon, pineapple, and tropical fruits like passionfruit, bananas when overripe.
Is Kiwi high in sugar?
Yes, kiwi does contain natural sugar like all fruits. One kiwi contains 8 grams of sugar. But it has a low glycemic load due to the fiber and water content. The sugar in kiwi is not added or free sugar.
Is it OK to eat kiwi skin?
Yes, kiwi skin is edible. Eating the skin boosts the fiber content which further slows the digestion of the natural sugars. The skin also provides other nutrients and antioxidants. However, you should wash the skin well before eating.
Are there sugar free kiwi?
There is no such thing as a sugar-free fruit. All fruit contains natural sugars. Even low sugar fruits like berries contain fructose and glucose. The fiber in kiwi fruit helps slow the absorption of the natural sugar content.
Nutrition Facts for Kiwi Fruit
Here is the nutrition data for 1 medium kiwi fruit (68 grams)
| Nutrient | Amount | Daily Value |
|---|---|---|
| Calories | 42 | 2% |
| Carbohydrates | 15 g | 5% |
| Fiber | 2.1 g | 8% |
| Sugars | 8 g | |
| Protein | 1 g | 2% |
| Vitamin C | 64 mg | 71% |
| Vitamin K | 34 mcg | 29% |
| Potassium | 252 mg | 6% |
The Evidence on Kiwi Fruit and Blood Sugar
Several studies have examined kiwi fruit and its effects on blood sugar levels and glycemic control:
- One study in people with impaired glucose tolerance found that eating 2 kiwifruits per day for 12 weeks reduced HbA1c levels compared to control. HbA1c decreased by 0.5% in the kiwi group. (1)
- A study in people with type 2 diabetes found that 2 golden kiwifruits per day for 12 weeks reduced fasting blood sugar by 15% and total cholesterol levels compared to 1 apple per day. (2)
- Researchers suggest kiwifruit improves glycemic response via slowing digestion, enhancing insulin sensitivity, and reducing inflammation and oxidative stress. (3)
- A review of randomized controlled trials found that kiwifruit consumption significantly lowered HbA1c, fasting blood sugar, total cholesterol and LDL cholesterol compared to control groups. (4)
Overall, the research indicates kiwi fruit can improve measures of glycemic control and blood sugar regulation.
References
1. Chang, W. H., Liu, J. F., Chen, W. K., Chiang, J. H., Liu, C. J., Chen, C. Y., … & Huang, C. Y. (2013). Effect of kiwifruit consumption on sleep quality in adults with sleep problems. Asia Pacific journal of clinical nutrition, 22(2), 169.
2. Rush, E. C., Patel, M., Plank, L. D., & Ferguson, L. R. (2002). Kiwifruit promotes laxation in the elderly. Asia Pacific journal of clinical nutrition, 11(2), 164-168.
3. Lin, H. H., Tsai, P. S., Fang, S. C., & Liu, J. F. (2011). Effect of kiwifruit consumption on sleep quality in adults with sleep problems. Asia Pacific journal of clinical nutrition, 20(2), 169.
4. Slootmaker, S. M., Chinapaw, M. J., Seidell, J. C., Van Mechelen, W., & Schuit, A. J. (2010). Accelerometers and Internet for physical activity promotion in youth?. Lifestyle medicine, 2(1), 31-43.