What is the nutritional composition of sugar?

The only nutrient present in refined sugar is simple carbohydrates (sucrose) with a caloric value of 398 kcal per 100 grams and it lacks proteins, fats, minerals, and vitamins.
Sugar is a source of calcium, iron, iodine, magnesium, zinc, and vitamins B12, B2, B3, A, D, and folates.
The consumption of sugar should be kept constant to maintain its level in the blood above the minimum.