If you have diabetes, bananas can be part of a healthy eating plan. Some tips may help reduce blood sugar spikes, including selecting an almost-ripe banana and eating it with other foods.

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When you have diabetes, it’s important to keep your blood sugar levels as stable as possible.

Good blood sugar management can help prevent or slow the progression of some of the main medical complications of diabetes.

For this reason, it’s essential to avoid or minimize foods that cause blood sugar spikes.

Despite being a healthy fruit, bananas are pretty high in both carbs and sugar, which are the main nutrients that raise blood sugar levels.

This article investigates whether you can eat bananas if you have diabetes and whether they affect your blood sugar.

If you have diabetes, being aware of the amount and type of carbs in your diet is important.

This is because carbs raise your blood sugar level more than other nutrients, which means they can greatly affect your blood sugar management.

When blood sugar levels rise in people without diabetes, their bodies produce insulin. This helps move sugar out of the blood and into cells, where it’s used or stored.

However, this process doesn’t work as it should in people with diabetes. Instead, either the body doesn’t produce enough insulin, or the cells are resistant to the insulin the body makes.

Without proper diabetes management, you may experience blood sugar spikes after eating high carb foods or have constantly high blood sugar levels, both of which are unhealthy.

How much sugar is in a banana?

One medium banana, which is about 126 grams (g), contains 29 g of carbs and 112 calories. The carbs are in the form of sugar, starch, and fiber.

A medium banana contains about 15 g of sugar.


Bananas contain simple carbs, which can cause blood sugar levels to rise more than other nutrients.

In addition to starch and sugar, a medium banana contains 3 g of fiber.

Everyone, including people with diabetes, should try to eat enough dietary fiber due to its potential health benefits.

However, fiber is especially important for people with diabetes because it can help slow the digestion and absorption of carbs.

This can reduce blood sugar spikes and improve overall blood sugar management.

One way to determine how a carb-containing food will affect blood sugars is to check its glycemic index (GI).

The GI ranks foods based on how much and how quickly they raise blood sugar levels.

The scores run from 0 to 100 with the following classifications:

  • Low GI: 55 or less
  • Medium GI: 56 to 69
  • High GI: 70 to 100

Diets based on low GI foods may be particularly good for people with type 2 diabetes.

This is because low GI foods are absorbed more slowly and cause a gradual rise in blood sugar levels rather than a large spike.

Overall, bananas score low to medium on the GI scale: 31 to 62, depending on the ripeness.


In addition to sugar and starch, bananas contain some fiber. This means your body digests and absorbs the sugars in bananas more slowly, which could prevent blood sugar spikes.

The amount of this type of carbs in a banana varies depending on the ripeness.

Green, or unripe, bananas contain less sugar and more resistant starch.

Resistant starches are long chains of glucose (starch) that are “resistant” to digestion in the upper part of your digestive system.

This means they function similarly to fiber and won’t cause a rise in blood sugar levels.

They also may help feed the friendly bacteria in your gut, which has a link with improved metabolic health and blood sugar management.

In fact, a small 2023 study of 17 adults with type 2 diabetes found that taking resistant starch, in the form of native banana starch, reduced fasting blood sugar and blood sugar spike. It also reduced hunger and increased feelings of fullness.

Other studies have indicated that resistant starch may have beneficial effects for people with type 2 diabetes, such as improving insulin sensitivity and reducing inflammation.

The role of resistant starch in type 1 diabetes is less clear.

A banana’s effect on blood sugar depends on its ripeness

Yellow, or ripe, bananas contain less resistant starch than green bananas, as well as more sugar, which is more quickly absorbed than starch.

This means fully ripe bananas have a higher GI and will cause your blood sugar to rise faster than green unripe bananas.


Green (unripe) bananas contain resistant starch, which doesn’t raise blood sugar levels and may improve long-term blood sugar management. Yellow (ripe) bananas contain more sugar, so they may cause a bigger rise in blood sugar.

Ripeness isn’t the only factor when it comes to the amount of sugar in your banana — size also matters. The bigger the banana, the more carbs you will be getting.

This means a larger banana will have a greater effect on your blood sugar levels. This portion-size effect is called the glycemic load.

Glycemic load is calculated by multiplying a food’s GI by the number of carbs in a serving and dividing by 100.

A score of less than 10 is considered low, 11 to 19 is moderate, and 20 or more is high.

The carb content of bananas varies by size, from about 18.5 to 35 g.

If a banana is fully ripe (with a GI of 62), its glycemic load could range from 11 for a very small banana to 22 for a very large banana.

Knowing the size of the banana you’re eating is important to ensure your blood sugar doesn’t rise too much.


The size of the banana you eat determines its effect on your blood sugar level. The larger the banana, the more carbs you’ll consume, and the greater the rise in your blood sugar will be.

Most general dietary guidelines for diabetes recommend following a healthy, balanced diet that includes fruit.

This is because eating fruits and vegetables has been linked to better health and a lower risk of conditions such as heart disease and some cancers.

People living with diabetes are at an even greater risk of heart disease and some cancers, so eating enough fruits and vegetables is important.

Unlike refined sugar products such as candy and cake, the carbs in fruits like bananas come with fiber, antioxidants, vitamins, and minerals.

More specifically, bananas provide fiber, potassium, vitamin B6, and vitamin C. They also contain some antioxidants and beneficial plant compounds.

For most people with diabetes, fruits — including bananas — are a healthy choice.

However, some people who are following very low carb diets need to watch their total carbohydrate intake to stay within their daily carb allotment. This means limiting foods higher in carbs, including bananas, when following a very low carb diet.

If your doctor says you can eat bananas, it’s important to be mindful of its ripeness and size to reduce its effect on your blood sugar level.


Fruits like bananas are healthy foods that contain fiber, vitamins, and minerals. You can usually include bananas in your diet even if you have diabetes. Check with your healthcare team before changing your eating plan.

How many bananas can a person with diabetes eat a day?

If you have diabetes, the amount of bananas you can eat a day depends entirely on you as an individual, your daily carbohydrate level, activity level, and how bananas affect your blood sugar.

Some people’s blood sugar levels may be more sensitive to bananas than others. Knowing how bananas affect your blood sugar can help you manage your medications and insulin injections, if necessary.

All in all, it’s best to consult a doctor or registered dietitian about including bananas in your diet.

Do bananas raise your blood sugar?

A banana will raise your blood sugar, but how much will depend on the size and ripeness of the banana, and the foods it is paired with.

The American Diabetes Association recommends eating bananas and other fruit as they contain fiber. It notes that eating fiber can help lower blood sugar levels.

You can enjoy bananas with healthy fats and protein to help minimize the blood sugar response.

What is the best fruit for people with diabetes?

The best fruit for people with diabetes is any fresh, frozen, or canned fruit without added sugar.

Including various fruit into your diet can help provide a variety of different vitamins, minerals, and antioxidants.

However, remember to be mindful of portion size. It’s best to limit fruit to a small piece of whole fruit or half cup portion size per meal or snack, and pair it with a protein or healthy fat source.

What foods can people with diabetes eat freely?

It is important to eat a balanced diet with a variety of nutrient-rich foods in portion sizes appropriate for meeting individualized nutrition goals.

Low carbohydrate whole foods that have a minimal effect on blood sugar can be beneficial for people with diabetes. These include:

  • nonstarchy vegetables, like cabbage, cucumber, and leafy greens
  • lean proteins, like chicken, fish, eggs, and tofu
  • healthy fats, like walnuts, avocados, and flaxseeds

However, even though a food is low carb, it doesn’t mean it is OK to eat it in large amounts every day. A diet with little variety can lead to nutrition deficiencies.

If you have diabetes, it’s possible to enjoy fruit such as bananas as part of a healthy eating plan.

If you enjoy bananas, the following tips could help minimize their effects on your blood sugar levels:

  • Watch your portion size: Eat a smaller banana to reduce the amount of sugar you eat in one sitting.
  • Choose a firm, nearly ripe banana: Pick one that’s not overly ripe so that the sugar content is slightly lower.
  • Spread your fruit intake throughout the day: Spread out your fruit intake to help reduce the glycemic load and keep your blood sugar levels stable.
  • Eat alongside other foods: Enjoy your bananas with other foods, such as nuts or plain Greek yogurt, to help slow the digestion and absorption of the sugar.

If you have diabetes, remember that carb-containing foods can affect people’s blood sugars differently.

Therefore, you might want to monitor how eating bananas affects your blood sugar and adjust your eating habits accordingly.