Which Banana Has the Least Calories? Size, Ripeness, and Nutrition Explained

An extra-small banana, under 6 inches long, contains approximately 72 calories, making it the lowest-calorie option among standard sizes. When considering which banana has the least calories for your diet, understanding that size is the most significant factor is crucial, although ripeness also plays a subtle role in its nutritional profile.

Quick Summary

The smallest banana has the fewest calories, while ripeness mainly affects the carbohydrate type. This article examines calorie counts across different sizes and explains how ripeness impacts nutrition and digestion.

Key Points

• Size is the Calorie Decider: The primary factor determining a banana's calorie count is its size; an extra-small banana has the fewest calories, approximately 72.

• Ripeness Impacts Carbs: The ripeness level affects whether a banana is primarily composed of resistant starch (green) or simple sugars (ripe), but the overall calorie total is very similar.

• Green Bananas Aid Gut Health: Unripe, green bananas are rich in resistant starch, which feeds beneficial gut bacteria and helps control blood sugar.

• Ripe Bananas Provide Quick Energy: Ripe, yellow bananas offer easily digestible sugars, making them a fast and effective energy source for activities.

• Nutrient-Dense Snack: Regardless of size or ripeness, all bananas are a healthy, low-fat source of potassium, fiber, and vitamins like B6 and C.

• Portion Control is Effective: When trying to manage calorie intake, selecting a smaller banana is the most straightforward and effective method.

• Focus on Dietary Goals: Choose a banana based on your specific needs, such as a green banana for blood sugar control or a ripe one for quick energy.

Size is the Most Important Factor for Calorie Count

When it comes to figuring out which banana has the least calories, the single most important factor is its size. The larger the banana, the higher its overall calorie content. The difference isn't due to varying nutritional density per gram, but simply because there's more fruit to consume. For individuals tracking their caloric intake, being mindful of portion size is far more effective than trying to find a specific variety of banana with fewer calories per gram.

Here is a general breakdown of average calorie counts for bananas of different sizes, based on USDA data:

• Extra small (shorter than 6 inches, approx. 81g): 72 calories
• Small (6–7 inches, approx. 101g): 90 calories
• Medium (7–8 inches, approx. 118g): 105 calories
• Large (8–9 inches, approx. 136g): 121 calories
• Extra large (9 inches or longer, approx. 152g): 135 calories

This makes the extra-small banana the clear winner for the fewest calories. However, all bananas are nutrient-dense and relatively low in calories compared to processed snacks, making them a great choice for a healthy diet regardless of size.

The Role of Ripeness: Starch vs. Sugar

Beyond size, the banana's ripeness affects its nutritional composition, particularly the type of carbohydrates it contains. While the total calorie count changes only negligibly with ripening, the way your body processes those calories is different.

• Green (Unripe) Bananas: These are rich in resistant starch, a type of carbohydrate that functions like soluble fiber. Resistant starch is not fully digested in the small intestine and instead ferments in the large intestine, feeding beneficial gut bacteria. This process promotes digestive health, slows the absorption of sugar into the bloodstream, and can increase feelings of fullness, all of which are beneficial for weight management. Due to their higher starch content, green bananas have a lower glycemic index (GI) score, meaning they cause a slower rise in blood sugar.

• Yellow (Ripe) Bananas: As a banana ripens, its resistant starch is converted into simple sugars, such as sucrose, fructose, and glucose. This conversion is what makes ripe bananas softer and sweeter. While this means a ripe banana contains more sugar than a green one, the overall calorie count remains very similar. Ripe bananas are more easily digested, making them an excellent and fast source of energy.

Comparing Unripe vs. Ripe Bananas

Feature	Green (Unripe) Banana	Yellow (Ripe) Banana
Texture	Firm and starchy	Soft and creamy
Taste	Less sweet	Much sweeter
Carbohydrates	High in resistant starch	High in simple sugars
Digestion	Slower, promotes gut health	Faster, quick energy source
Glycemic Index	Lower (around 42)	Higher (around 51)
Benefits	Better for blood sugar control, satiety	Good for quick energy, easier digestion

Nutrient-Dense Regardless of Calorie Count

Whether you choose a small, green banana or a large, ripe one, you're getting a powerful dose of essential nutrients. Bananas are particularly well-known for their potassium content, which is vital for heart health and maintaining proper fluid balance in the body. A medium banana provides about 9% of the daily value for potassium.

Beyond potassium, bananas offer a range of other vitamins and minerals, including:

• Vitamin B6: Important for metabolism, nervous system function, and red blood cell production.
• Vitamin C: A key antioxidant that supports immune function and skin health.
• Fiber: Supports digestive health and promotes feelings of fullness.
• Manganese: Plays a role in bone formation and metabolism.

For those on a weight management journey, incorporating bananas can be highly beneficial. Their fiber content helps promote fullness, which can prevent overeating. Combining a banana with a protein or healthy fat source, like nuts or yogurt, can further enhance satiety and provide a more balanced snack.

Choosing the Right Banana for Your Goals

For most people, the decision of which banana to eat should be based on personal preference and dietary goals, rather than a minimal calorie difference. If your main goal is to control blood sugar levels or maximize feelings of fullness, opting for a less ripe, smaller banana is a good strategy. If you need a quick energy boost for a workout or prefer a sweeter snack, a ripe, medium-sized banana is an excellent choice.

Ultimately, all bananas are a healthy, nutritious addition to any diet. The key takeaway is to select the smallest size available if minimizing calories is your primary concern, and to consider the ripeness if you're focused on resistant starch or a lower glycemic impact.

Conclusion

In summary, the smallest banana, specifically an extra-small one, will have the fewest calories, at around 72 calories. However, the difference between a small and a medium banana is minor. The ripeness of a banana affects the type of carbohydrates it contains (more resistant starch when green, more sugar when ripe), but the total calorie count is not significantly impacted. All bananas are packed with valuable nutrients like potassium, fiber, and vitamins, making them a healthy choice for any diet. For the lowest calorie option, simply choose the smallest banana you can find.

References

• Metropolis Healthcare. "1 Banana Calories, Protein & Nutritional Value Explained." Accessed Oct 6, 2025. https://www.metropolisindia.com/blog/preventive-healthcare/banana-calories-protein
• Healthline. "How Many Calories and Carbs Are in a Banana?" Accessed Oct 6, 2025. https://www.healthline.com/nutrition/bananas-calories-carbs
• Verywell Fit. "Banana Nutrition Facts and Health Benefits." Accessed Oct 6, 2025. https://www.verywellfit.com/are-bananas-bad-for-weight-loss-3495634
• Ro.co. "How Many Calories Are There in a Banana?" Accessed Oct 6, 2025. https://ro.co/weight-loss/banana-calories/
• Food Network. "How Many Calories Are In a Banana?" Accessed Oct 6, 2025. https://www.foodnetwork.com/how-to/packages/food-network-essentials/how-many-calories-in-a-banana
• The Nutrition Source (Harvard T.H. Chan School of Public Health). "Bananas." Accessed Oct 6, 2025. https://nutritionsource.hsph.harvard.edu/food-features/bananas/

Key Takeaways

• Size Matters Most: The smallest banana has the fewest calories, with an extra-small banana containing around 72 calories.
• Ripeness Affects Carbs: As a banana ripens, its carbohydrates change from resistant starch to simple sugars, but the overall calorie count doesn't change significantly.
• Green is Better for Blood Sugar: Unripe, green bananas are higher in resistant starch, which helps manage blood sugar levels and increases satiety.
• Ripe for Quick Energy: Ripe, yellow bananas offer a faster energy source due to their higher sugar content, which is easily digestible.
• Still a Healthy Choice: Regardless of size or ripeness, all bananas are low in fat and packed with essential nutrients like potassium, vitamin B6, and fiber.
• Portion Control is Key: To minimize calorie intake, focus on choosing a smaller banana rather than worrying about the type or ripeness.

FAQs

• What is the lowest calorie banana? The lowest calorie banana is the smallest one. An extra-small banana, under 6 inches long, contains approximately 72 calories.

• Do green bananas have fewer calories than ripe bananas? No, the total calorie content is nearly identical. The key difference is that green bananas contain more resistant starch, while ripe bananas have more simple sugars.

• How many calories are in a medium banana? A medium banana, which is typically 7 to 8 inches long, contains about 105 calories.

• Are bananas good for weight loss? Yes, bananas can be a great addition to a weight loss diet. Their fiber content helps you feel full, and they provide sustained energy. Choosing smaller bananas can help manage calorie intake.

• Why is ripeness important if the calories are the same? Ripeness is important because it changes the type of carbohydrate. Green bananas are better for blood sugar management and gut health due to their resistant starch, while ripe bananas offer a quicker energy source.

• Does mashing or slicing a banana change its calorie count? No, preparing a banana by mashing or slicing does not change the total calories of the fruit itself. However, a cup of mashed banana has more calories than a cup of sliced banana because a mashed cup contains more banana by weight.

• What is resistant starch, and why is it beneficial? Resistant starch is a type of carbohydrate in unripe bananas that is not easily digested. It acts like fiber, feeding good gut bacteria and slowing sugar absorption, which is beneficial for blood sugar control and satiety.

• Can bananas raise my blood sugar? Yes, as bananas ripen and the resistant starch turns to sugar, they have a moderate glycemic index and can cause a temporary rise in blood sugar. Green bananas have a lower GI, and pairing any banana with a fat or protein source can help moderate blood sugar spikes.

• Should I avoid bananas because they contain sugar? No, the sugar in bananas is natural fruit sugar balanced by fiber, vitamins, and minerals. They are a much healthier option than processed sweets with added sugar and offer significant nutritional benefits.

Frequently Asked Questions

What is the lowest calorie banana?

The lowest calorie banana is the smallest one. An extra-small banana, under 6 inches long, contains approximately 72 calories.

Do green bananas have fewer calories than ripe bananas?

No, the total calorie content is nearly identical. The key difference is that green bananas contain more resistant starch, while ripe bananas have more simple sugars, but the calorie count per banana is not significantly different.

How many calories are in a medium banana?

A medium banana, which is typically 7 to 8 inches long and weighs about 118 grams, contains about 105 calories.

Are bananas good for weight loss?

Yes, bananas can be a great addition to a weight loss diet. Their fiber content helps you feel full, and they provide sustained energy. Choosing smaller bananas can help manage calorie intake more easily.

Why is ripeness important if the calories are the same?

Ripeness is important because it changes the type of carbohydrate. Green bananas are better for blood sugar management and gut health due to their resistant starch, while ripe bananas offer a quicker energy source for activities.

Does mashing or slicing a banana change its calorie count?

No, preparing a banana by mashing or slicing does not change the total calories of the fruit itself. However, a cup of mashed banana has more calories than a cup of sliced banana because a mashed cup contains more banana by weight.

What is resistant starch, and why is it beneficial?

Resistant starch is a type of carbohydrate in unripe bananas that is not easily digested. It acts like fiber, feeding good gut bacteria and slowing sugar absorption, which is beneficial for blood sugar control and satiety.