Moderately so ...
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Bananas (one 136g serving, 1 whole) have only 30 grams. That is a moderate amount of carbohydrate considering it's a high volume food.
They also have 3 grams of fiber per serving and since fiber counts as a carb that means that bananas have only 27 grams of carbs per serving - fiber doesn't go into the bloodstream and affect your insulin or get stored as fat which is why it doesn't count as a carb.
It doesn't matter what diet you're on, in my book that counts as a moderate-carb food which means you can eat fruit like bananas and enjoy in moderation.
You would need to eat a large one just to reach your carb limit on a Keto diet, which is low if you compare it to other carbohydrates like whole grains.
Controlling insulin is key when it comes to losing weight and good health and adding in bananas ensures that you are as safe as can be with that food group.
Eat and be healthy.
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