**1. Introduction**

Garlic is widely used around the world for its pungent flavour as a seasoning or condiment. From the history, it is known that garlic has been used for more than 7,000 years by humans. Originally the plant was native to central Asia [1], but it has long been used for consumption (raw or cooked) as seasoning in many other parts of the world such as the Mediterranean region, Africa, and Europe. It has specifically been used for its medicinal purposes in ancient Egypt. [2].

The garlic plant's bulb is the most commonly used part of the plant. As mentioned, garlic or more specifically the cloves is believed to have many medicinal properties ranging from positively affecting anything such as high blood pressure (BP) and lowering cholesterol to using it as a treatment for the common cold [3]. Even Hippocrates, Galen, and Dioscorides all mention the use of garlic for many conditions, including parasites, respiratory problems, poor digestion, and low energy [4].

Plants have always been the sources of important medicines since time immemorial. Currently there is a huge movement and emphasis towards scientifically and clinically unlocking the value of traditional phytomedicines in the service of humanity. With this in mind the scope of this chapter is to investigate garlic's effects on human health with special reference to the effect on the reproductive system. The chapter will furthermore aim to explain the mechanisms via which garlic can exert its effect.

© 2014 Valente et al.; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
