Often used and well known for the ability to increase milk production in a lactating mother by boosting the hormone estrogen. This benefits both the baby and the mother. Fennel can also be used as a natural laxative for chronic and acute constipation. Unlike synthetic laxatives, it has no side effects and can be used daily. It also can help the stomach stay healthy and protects it from infections. Fennel can also kill parasitic worms. Fennel oil reduces obesity, wrinkles on the skin, and can be used to treat insect bites and colic, nausea, vomiting, anorexia, hiccups, dyspepsia, rheumatism and excess cellulite. Fennel should not be used on those suffering from epilepsy.