What is Garlic? Garlic is a member of the onion (Allium) family, & is used (in fresh or dried form) as a source of characteristic sulphur containing chemical compounds (e.g. allicin, which is responsible for the odour of garlic), that have various actions within the body. Some of these compounds are present in garlic in a latent form, which are activated when garlic cloves are crushed or digested. What Does Garlic Do? May help to maintain a healthy heart & circulation May help to maintain a healthy immune system.