Is it bad to eat the dark part of a banana?

January 13, 2026 •

4 min read

According to the FDA, in most cases, it is perfectly safe to eat a ripe or even overripe banana, including the dark parts, as long as it is not visibly moldy. The dark spots, whether on the peel or the flesh, are usually a natural sign of ripening and not an indication of spoilage. However, there are a few rare instances where caution is advised.

Quick Summary

The dark parts of a banana are generally safe and edible, often indicating ripeness and higher sugar content. These spots are caused by enzymatic browning and bruising, but not spoilage. Proper handling and observing signs like mold or a fermented smell are key to ensuring safety. Use overripe bananas for baking or smoothies.

Key Points

Dark parts are usually harmless: The brown spots or streaks in a banana's flesh are typically due to enzymatic browning and harmless bruising, signifying ripeness.
Look for signs of spoilage: Avoid eating bananas that have visible mold, a fermented or rotten smell, or are leaking fluid.
The center seeds are edible: The small black dots often seen down the center are immature, infertile seeds and are completely safe to consume.
Ripe bananas are healthier in some ways: Fully ripe, dark-spotted bananas contain higher levels of antioxidants and compounds like Tumor Necrosis Factor (TNF).
Overripe bananas are great for cooking: Very ripe bananas, even with extensive browning, are excellent for baking, smoothies, or freezing, provided they don't show signs of spoilage.
Some diseases are harmless to humans: Rare fungal infections can cause discolored cores, but they are not generally considered a health threat to humans, though they may cause stomach upset.

What Causes Dark Spots in a Banana?

The dark patches or streaks that can appear in a banana's flesh and on its peel are primarily the result of three different, and mostly harmless, processes. Understanding these can help you confidently decide if your banana is okay to eat or should be composted.

Enzymatic Browning

This is the most common reason for browning and blackening in bananas. As bananas ripen, they produce ethylene gas, a hormone that triggers the ripening process. This gas causes the yellow pigments to break down and the fruit's starch to convert into sugar, making it softer and sweeter. A specific enzyme called polyphenol oxidase (PPO) reacts with phenolic compounds in the presence of oxygen, forming melanin—the same dark brown pigment found in human skin. This reaction is why a banana peel's speckles grow larger and the fruit's interior browns over time.

Bruising and Mechanical Damage

Rough handling during harvesting, transportation, or even at home can cause bruising. When a banana is bumped or dropped, the cell membranes in that spot rupture. This allows the PPO enzyme to mix with phenolic compounds and oxygen more rapidly in that localized area, causing it to darken quickly. This type of discoloration is usually concentrated and localized, and the surrounding flesh remains firm and edible. The condition is sometimes referred to as 'black center syndrome' when it occurs internally due to mishandling.

Immature Seeds

In the center of commercial bananas, you can often see three distinct lines of tiny black dots. These are not fully developed seeds, but rather the remnants of infertile ovules. As the banana ripens, these seed remnants tend to darken along with the rest of the fruit, sometimes appearing darker earlier, but they are completely edible and harmless. Wild banana varieties, in contrast, contain large, hard, viable seeds.

When is it not safe to eat a dark banana?

While most dark banana parts are safe, there are clear signs of true spoilage that indicate it's time to throw the fruit away.

Signs of a Truly Spoiled Banana

Visible Mold: If you see any fuzzy, white, gray, or greenish mold on the banana—inside or out—it's time to discard it.
Rotten or Fermented Smell: A bad banana will start to smell sour, fermented, or alcoholic, indicating that the sugars are breaking down into alcohol.
Mushy, Leaking Flesh: The banana should feel soft, but not mushy or liquidy. If it's leaking fluid or is completely black and mushy inside, it has gone bad.
Unusual Coloration: Certain rare fungal infections, such as Nigrospora (which causes squirter disease), can turn the core a dark red or brown. While not always toxic to humans, it can cause gastrointestinal upset, so it's best to avoid.

Summary of Safe vs. Spoiled Banana


Feature	Safe (Ripe)	Spoiled (Rotten)
Appearance	Yellow peel with scattered dark brown speckles or spots. Dark center seeds visible. Minor dark bruises can be cut away.	Entirely black peel, or black and mushy inside. Visible fuzzy white, gray, or green mold.
Texture	Soft, but not mushy. Easily mashed with a fork.	Excessively soft and squishy, often with a translucent appearance. Leaking fluids.
Smell	Sweet, strong banana aroma.	Pungent, fermented, or rotten smell. Off-odors present.
Usage	Great for smoothies, baking, or eating raw for a sweet, concentrated flavor.	Discarded, or composted. Should not be consumed, even for baking.

The Health Benefits of Ripe Bananas

Far from being bad, consuming fully ripe bananas with dark spots can actually offer some health benefits.

Increased Antioxidants: The enzymes that cause browning also contribute to an increase in antioxidants in the fruit.
Cancer-Fighting Properties: Research from Japan has indicated that fully ripe bananas with dark spots contain a substance called Tumor Necrosis Factor (TNF), which helps boost the body's immunity and can fight against abnormal cells.
Easier Digestion: As bananas ripen, the complex starches convert into simple sugars, making them much easier for the body to digest.
Rich in Nutrients: Ripe bananas are a great source of essential nutrients like potassium, Vitamin C, and fiber.

Conclusion

The dark parts of a banana are overwhelmingly safe to eat. They are a natural and often beneficial result of the ripening process, caused by enzymatic browning or minor bruising. In fact, a speckled or soft banana is sweeter and contains higher levels of certain antioxidants and other beneficial compounds than a green one. However, the key to safety lies in using your senses. A banana that has gone bad will have other telltale signs, such as a fermented smell, visible mold, or a slimy texture. When in doubt, it's always best to be cautious and throw it out. For bananas that are just a little too ripe for your taste, baking them into banana bread or blending them into a smoothie is an excellent way to use them up.

For more detailed information on banana ripening and food safety, you can consult resources like EatingWell's guide on brown bananas: Is It Safe to Eat Brown Bananas?.

Frequently Asked Questions

Yes, if the inside is not black and there is no mold or fermented smell, it is safe. The black peel simply indicates extreme ripeness. The banana will be very soft and sweet and is best used for baking or smoothies.

No, a bruised banana will not make you sick. The darkened spots are just oxidized flesh from physical damage. You can simply cut away the bruised parts and eat the rest of the banana.

Black center syndrome is a condition caused by rough handling or stress during transport, which causes the banana to ripen from the inside out. While it can result in a hard or crunchy texture, it's not a safety concern.

Yes, as a banana ripens and develops dark spots, its starch is converted to sugar. This results in a softer texture and a sweeter, more intense flavor than a less ripe banana.

It is best to discard a banana with dark red streaks. While often caused by harmless fungal infections like Nigrospora, it can cause gastrointestinal upset, and it's not worth the risk.

Check for mold, an alcohol-like smell, or a leaky, overly mushy texture. If these signs are present, the banana is rotten. Simple dark spots and sweet aroma indicate ripeness.

Some research, particularly from Japan, has suggested that fully ripe bananas with dark spots have elevated levels of Tumor Necrosis Factor (TNF), a substance with anti-cancer properties that boosts immunity.