For sure ...
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Bananas (one 136g serving, 1 whole) contain 30 grams of carbohydrate and almost no fat.
Some of that carbohydrate (3.0g) is fiber which means that bananas have pretty much no fat and a moderate amount of carbs.
They have 1.5 grams of protein in a whole serving and tons of nutrients. Fruit is usually frowned upon when it comes to weight loss but moderate amounts are generally fine.
A banana a day as the saying goes, has never been cause for anyone to gain weight or to not 'lose' any bodyfat.
You would need to eat about 20 bananas per day to maintain your body weight so technically I guess it's possible to gain weight with bananas if you were to eat 30+/day, everyday, but good luck with that feat.
Eat and be healthy.
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