Riper bananas have less fiber, but more antioxidants
A banana’s ripening involves the conversion of resistant starch into the sugars fructose and glucose. Even if the calories remain the same (about 90 kcal per banana), this means that there are differences in how the sugars will be digested, with riper bananas raising blood sugar faster.
The glycemic index (how fast the banana your raises blood sugar) is, however, always relatively low. Resistant starch, found in higher quantities in unripe bananas, is a fiber which can’t be digested and is instead fermented by your large intestine bacteria, and is believed to have beneficial effects on intestinal health, though more research is needed to secure this point.
Ripe bananas, however, do have the advantage of higher amounts of antioxidants known as catechins, which are known to reduce the risk of heart disease.
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