Rosemary Oil on Amazon Boosts Hair Growth, Say Shoppers.

The Handcraft Blends Rosemary Essential Oil, which is on sale for $17 on Amazon, has nearly 65,000 recommendations from shoppers who claim their hair is "dramatically growing and getting fuller" after using it. The oil comes in a 4-ounce glass bottle with a dropper top for easy application and can be left on the scalp for an hour to overnight before washing out. Studies have shown that rosemary oil can improve hair health and stimulate growth after six months.