Because the production of some types of food supplements through many steps must be made to have high production costs. Making the supplements are expensive, with costs of production.
Since the production of certain supplements through many steps, making production costs higher. The food supplement is expensive as the cost of production.
Due to the production of some types of dietary supplements must go through many steps to make the production cost is high. The price is too expensive, too, according to supplement the cost of production.