Not so much ...
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Mustard Greens (one 140g serving) have only 3 grams. That is a very low amount of carbohydrate considering it's a high volume food.
They also have 2.8 grams of fiber per serving and since fiber counts as a carb that means that mustard greens have only 0.2 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 low-carb food which means you can eat as much mustard greens as you like and not worry about it.
You would need to eat 10+ cups of the stuff just to reach your carb limit on a Keto diet, that's how little carbs it has. I don't know anyone who eats that much mustard greens in a day.
Controlling insulin is key when it comes to losing weight and good health and adding in mustard greens ensures that you are as safe as can be with that food group.
Eat and be healthy.
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