Not really ...
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Tomatoes (one 180g serving) have only 7 grams. That is a very low amount of carbohydrate considering it's a high volume food.
They also have 2 grams of fiber per serving and since fiber counts as a carb that means that tomatoes have only 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 many servings of tomatoes as you like and not worry about it.
You would need to eat 3+ 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 tomato in a day.
Controlling insulin is key when it comes to losing weight and good health and adding in tomatoes ensures that you are as safe as can be with that food group.
Eat and be healthy.
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