When you’re in the mood for something sweet, fruit is the most nutritious option by far. But if you’re eating for stable blood sugar, you may discover that some fruits cause a significant spike while others result in more subtle elevations. What gives? And do you have to give up fruit altogether if your goal is minimizing glycemic variability?
First, it’s important to understand that no natural food—including fruit—is inherently bad. The overall composition of your meals matters more than any individual component when it comes to your health. Plus, fruits offer fiber and a range of vitamins, minerals, phytochemicals, and antioxidants, all of which have benefits. In fact, some fruits are incredible sources of micronutrients that are essential for overall health and optimal cellular function.
Berries, for example, are one of the top dietary sources of polyphenols (a category of plant chemical) called anthocyanins. These bluish-purple plant pigments have been shown to counteract disease-causing oxidative stress and help alleviate or reduce the risk of conditions such as obesity, diabetes, and cardiovascular disease.
And in addition to high levels of immune-supporting vitamin C, citrus fruits contain at least 19 different flavonoid compounds. Collectively dubbed “citrus flavonoids,” their ability to help regulate biochemical pathways that enhance lipid metabolism, reduce blood glucose, improve insulin sensitivity, and reduce oxidative stress may offer antidiabetic benefits.
As these two examples suggest, you could spend hours researching every fruit’s entire nutritional profile and possible health benefits. But when your goal is balanced blood sugar, three fundamental factors matter most. The extent to which a particular fruit spikes your blood sugar depends primarily on:
- How much sugar is in the fruit. Most whole fruits contain three types of sugar—glucose, fructose, and sucrose—in varying proportions. All can increase blood sugar levels and can result in adverse metabolic effects when consumed in excess. (Fructose is metabolized in the liver and causes a smaller initial increase in blood glucose, but consuming too much can lead to fat buildup in the liver and insulin resistance of liver cells.) Rather than focusing on one type of sugar, compare the overall sugar content of fruits. For example, a medium banana has 14.4 grams of sugar, while a 1/2 cup of raspberries has just 2.7 grams.
- How much fiber is in the fruit. A portion of fiber passes through the digestive system intact. Soluble fiber helps slow down digestion and the rate at which the gut absorbs glucose—which, in turn, can buffer elevations in blood sugar. In our example, the banana has 3.1 grams of fiber, and the raspberries have 4 grams.
- The glycemic index of the fruit. Glycemic index (GI) uses a scale of 0-100 to indicate how a particular food impacts blood sugar. Generally, the body processes foods with higher GI values more quickly, resulting in more rapid and sharp rises in blood glucose. However, GI is a bit of a crude measure that doesn’t take into account individuality in glucose response, so use it only as a reference point, not as definitive. While many whole fruits fall into the “low” or “moderate” GI categories (scores of 69 or less), certain fruits have even lower GIs than others. For example, a typical banana clocks in at 47 (or up to 57 when overripe), while a little more than a cup of raspberries has a GI of 32. However, keep in mind that the glycemic index only tells you about the potential glucose impact of a food eaten alone—combine fruit with foods rich in protein, fat, and fiber, and the glycemic effect of your snack will be less extreme. (More on this below.)
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What Else Determines How Much a Fruit Spikes Your Blood Sugar?
A fruit’s nutritional profile can reveal a lot, but it isn’t the whole picture. A few other factors can have a significant impact on blood sugar balance:
- The ripeness of the fruit. Because fruit starches are converted to sugar as the fruit matures, ripe fruit contains more sugar (in the form of glucose, fructose, and sucrose) and has a higher GI than unripe fruit. Certain fruits—such as berries, citrus, and grapes—stop ripening once they’re picked. But others—such as bananas, kiwis, pears, mangos, and stone fruits—continue ripening as they sit on your kitchen counter (and even as they sit in the fridge, although this slows ripening significantly). Eating these “climacteric fruits” before they fully ripen can lower your sugar intake. For example, in one analysis, ripe bananas contained around 15 grams of combined glucose and fructose, while unripe green bananas contained just 3.2 grams. Unripe bananas are also a good source of resistant starch, which has metabolic benefits.
- How you’re consuming it. Fresh, whole fruit is always best for blood sugar control and overall metabolic health. Though convenient, dried fruit is devoid of its filling water content and much easier to overeat because of its smaller volume, increasing the amount of sugar you consume. Blending a smoothie breaks down the fibrous structure of the fruit. Since your body doesn’t have to do that work, sipping your fruit leads to quicker digestion and absorption of sugars and, therefore, more significant elevations in blood sugar. But the worst offenders are juices, as they lack all fiber. This speeds up the absorption of sugar, potentially causing a blood sugar spike. In fact, drinking one or more 8-ounce servings of fruit juice every day may increase Type 2 diabetes risk by up to 21%, while eating at least two servings of whole fresh fruits per week may reduce the risk.
- What you’re eating with it. Pairing fruit with a source of fat, protein, or fiber (think: plain yogurt, cheese, walnuts, peanut butter, chia seeds, flax seeds, olives, avocado, or unsweetened protein powder) can help curb a blood sugar spike. That’s because fiber largely passes through the digestive system intact and interferes with the absorption of sugar from fruit, while protein and fat slow gastric emptying (the rate at which food passes from the stomach to the intestines), thereby slowing the absorption of sugar into the bloodstream. Avoid pairing fruit with added sugars or refined grains—like adding banana slices to cereal, sprinkling grapefruit with sugar, or drizzling honey on berries—as that will only spike blood sugar more.
- When you’re eating it. Blood glucose is more likely to spike if you eat carbohydrates first. In one small study, people with Type 2 diabetes consumed two meals 15 minutes apart. The first meal consisted of skinless grilled chicken breast, salad with vinaigrette, and steamed broccoli with butter, while the second meal was bread and orange juice. Eating the chicken meal before the bread and OJ led to 37% lower glucose levels an hour after eating compared to eating the meals in the reverse order. Insulin levels were also lower when subjects consumed the protein, veggies, and fats before the carbohydrates. So when you plan to have fruit as dessert, center your meal on high-quality protein and healthy fats.
- Your individual response. Everything from the composition of your gut microbiome to your genetics and even your stress levels, sleep quality, and physical activity contributes to the way your body responds to foods and processes nutrients. This is why you may be able to eat mango and have a moderate rise in blood sugar, but your friend’s levels skyrocket after mango. The more you know about your body’s unique response—by paying attention to how you feel after eating or checking your blood sugar with a glucometer or continuous glucose monitor (CGM)—the easier it is to make healthy choices.
- How much you eat. Portion size still matters. A small (and less-ripe) banana may not cause as much of a blood sugar spike as a large (and overripe) banana. One reason: They can differ in sugar content by 9 grams or more. If you’re unsure how certain foods will affect you, keep portions small while monitoring your glucose response.
5 Best Fruits for Blood Sugar
With all of this in mind, let’s look at how some common fruits impact blood sugar.
First up: the best options. These fruits (and their close relatives) tend to have a relatively mild impact on blood sugar and contain beneficial polyphenol compounds—including anthocyanins and flavonoids—that may help improve insulin sensitivity and reduce blood glucose through a variety of mechanisms.
Raspberries, 1/2 cup
- Sugar: 2.7 grams
- Fiber: 4 grams
- Glycemic index: 32
- Levels Zone score: 7.0 (paired with yogurt: 8.5)*
- Avg glucose rise: 22 mg/dL
Raspberries provide a fair amount of fiber for relatively little sugar. Plus, they’re high in a specific category of polyphenols called anthocyanins, which have anti-inflammatory and antioxidant properties. Studies suggest that eating berries (many rich in anthocyanins, especially more blue or purple varieties) may help decrease post-meal glucose spikes and increase insulin sensitivity. In the lab, they appear to promote the growth of insulin-producing cells and increase glucose uptake by cells. Since blackberries, blueberries, and strawberries are also unlikely to spike your blood sugar, keep berries in your kitchen rotation. They’re delicious on their own or paired with nuts or chia seeds.
Orange, 1 medium fruit
- Sugar: 12 grams
- Fiber: 2.8 grams
- Glycemic index: 43
- Levels Zone Score: 6.2 (Grapefruit: 6.6)
- Avg glucose rise: 27 mg/dL
Oranges have a moderate sugar content and a decent amount of fiber. They also have around 9% of the recommended dietary allowance for folate (vitamin B9), which aids in metabolism. They contain numerous flavonoid compounds that appear to support lipid and glucose metabolism, lower inflammation, and counter oxidative stress. Or consider another citrus: Grapefruits contain even less sugar (8.5 grams per half fruit) than oranges, and slightly less fiber, so they’re also unlikely to spike blood sugar. And lemons and limes contain only 1-2 grams of sugar per fruit, so their impact is negligible. Snack on oranges plain or add a few segments to a salad topped with lean protein.
Apple, 1 medium fruit
- Sugar: 19 grams
- Fiber: 4.4 grams
- Glycemic index: 36
- Levels Zone score: 6.5-7 (with peanut or almond butter: 7.5)
- Avg glucose rise: 27 mg/dL
While apples contain a fair amount of sugar, their fiber content helps balance this. Be sure to leave the peel on: The skin is a good source of polyphenols such as quercetin, which has anti-inflammatory and antioxidant properties and may support healthy blood glucose and blood lipids, according to preliminary animal research. Even better, apples pair well with a variety of protein- and fat-containing foods—such as cheese, peanut butter, nuts, seeds, or deli turkey—that can slow the absorption of sugar into your bloodstream. Most varieties of apples have similar nutritional profiles, and the USDA nutritional analysis is based on data for red delicious, golden delicious, gala, granny smith, and fuji varieties.
Kiwi, 1 fruit
- Sugar: 6.7 grams
- Fiber: 2.3 grams
- Glycemic index: 52
- Levels Zone score: 6.5
- Avg glucose rise 26 mg/dL
Kiwis are relatively low in sugar with a decent amount of fiber. They also contain a range of beneficial antioxidants such as vitamins C and E, lutein, zeaxanthin, beta-carotene, and chlorophylls—and research suggests antioxidants such as those found in kiwis have the potential to help counteract inflammatory processes and oxidative stress in the body. The total antioxidant content of kiwis clocks in above apples and grapefruit but below some berries and oranges. Make kiwis even more blood sugar-friendly by eating the skin, which increases fiber content by about 50% and boosts vitamin E and folate by about a third.
Coconut, 1 ounce unsweetened flakes
- Sugar: 2 grams
- Fiber: 4.6 grams
- Glycemic index: 42
- Levels zone score: 8
- Avg glucose rise: 17 mg/dL
Unsweetened dried coconut flakes have more fiber than sugar. And thanks to their fiber and fat content, they can even help dampen your blood sugar response to other fruits. Coconut also contains a good amount of the mineral manganese, which activates enzymes needed for glucose and fat metabolism, along with some selenium, which mimics the beneficial effects of insulin and promotes the absorption of glucose from the bloodstream into cells. And coconut is an option to add a hint of sweetness to meals or snacks without adding much sugar.
5 Worst Fruits for Blood Sugar
These fruits tend to have a greater impact on blood sugar. Try to limit them in your diet or follow our suggestions to promote a more gradual rise in blood glucose.
Bananas, 1 medium fruit
- Sugar: 14.4 grams
- Fiber: 3.1 grams
- Glycemic index: 51
- Levels zone score: 5.7 (with peanut butter: 7.3)
- Avg glucose rise: 34 mg/dL
Because a banana’s starch is converted to sugar as it ripens, very ripe bananas have the most significant impact on blood sugar: Their GI can jump into the mid-range at 57, making them a bit more likely to trigger a spike. Eating a banana that hasn’t browned yet with nut butter or after a meal containing protein and fats can help reduce this effect. And if you can handle the slightly bitter taste and firmer texture, green bananas are a good choice. They may contain up to 10 grams less sugar and a form of glycemic-friendly starch called resistant starch, which has been linked to improved insulin sensitivity and increased satiety. Since the small intestine doesn’t digest resistant starch, it passes to the colon, where it functions as a prebiotic fiber, feeding “good” bacteria and leading to a slight rise in blood sugar.
Grapes, 1 cup (green)
- Sugar: 23.4 grams
- Fiber: 1.4 grams
- Glycemic index: 54
- Levels Zone score: 5.1
- Avg glucose rise: 38 mg/dL
Grapes contain a hefty dose of sugar with minimal fiber, and as a result, they may sharply raise blood sugar. While they have some beneficial micronutrients, including various polyphenols, they’re not as rich in these compounds as berries. Consider replacing grapes with berries or buffering a blood sugar spike by incorporating small amounts of grapes into meals, such as slicing up a few to add to chicken salad.
Mangos, 1 cup
- Sugar: 22.6 grams
- Fiber: 2.6 grams
- Glycemic index: 51
- Levels Zone score: 6
- Avg glucose rise: 32 mg/dL
Like many tropical fruits, mangoes pack a lot of sugar and not enough fiber to significantly offset a rise in blood sugar. Even worse, blending frozen mango into smoothies breaks down that fiber, often leading to more significant blood sugar spikes. Mangoes aren’t without micronutrients, though, as they’re a decent source of folate and polyphenols, and a cup provides more than half the RDA for vitamins C and A. If you want to enjoy mango, eat it after a meal and keep your serving size small.
Pineapple, 1 cup
- Sugar: 16.3 grams
- Fiber: 2.3 grams
- Glycemic index: 59
- Levels Zone score: 5.6
- Avg glucose rise: 34 mg/dL
While most fruits on this list have a low glycemic index, pineapple’s GI is in the mid-range, which means it may be more likely to spike blood sugar. However, a cup of pineapple delivers almost a day’s worth of vitamin C for men and a full day’s worth for women, as well as some polyphenols. If you want a pineapple fix, eat it after a meal and keep your serving size small, or use it to make pineapple salsa to spread over meats and fish.
Medjool dates, 1 date
- Sugar: 16 grams
- Fiber: 1.6 grams
- Glycemic index: 55
- Levels Zone score: 5.5
- Avg glucose rise: 35 mg/dL
Given the high sugar content of just one date, these fruits aren’t meant for snacking. However, in the context of using a small number of dates as a natural sweetener in desserts, this fruit (and other whole-food sweeteners) is a better choice than table sugar: it has a lower glycemic index, and its sugar comes packaged with a small amount of fiber, vitamins, and minerals.
* The numbers here represent anonymous aggregate data based on Levels members’ food logs and CGM data. A Zone Score is a score of 1-10 based on the glucose peak and rise from baseline.