Some carbs are simple, like sugar. Other carbs are complex, like those found in beans, nuts, vegetables, and whole grains. Complex carbohydrates are better for you because they take longer for your body to digest. They give you steady energy and fiber.ome carbs are simple, like sugar. Other carbs are complex, like those found in beans, nuts, vegetables, and whole grains. Complex carbohydrates are better for you because they take longer for your body to digest. They give you steady energy and fiber.