Honey-based treatments cough remedies are commonly used across the world. Folk medicine recommends honey for many ailments, and lime has been listed in Indian traditional medicine as a cough treatment. Currently, there are no scientific studies to support the combination honey and lime as a cough remedy. However, properties of these substances may contribute to the anecdotal claims of benefit.
Lime is a citrus fruit, and contains beneficial compounds such as vitamin C, beta-carotene, flavonoids, limonoids and folic acid. Lime and lemon juice have more citric acid than other citrus fruits. As an acid, it has the proposed ability to break up mucus, if the cough is productive.
Honey is also acidic. It has a thick consistency and is full of moisture, two aspects that assist wound healing. The consistency of honey may offer relief for a cough-irritated throat. In an Archives of Pediatrics & Adolescent Medicine December 2007 study, parents rated honey over cough syrup or no treatment for symptomatic relief of their child’s nocturnal cough.
Antimicrobial Properties of Lime & Honey
The recommendation for lime and honey for a cough may go beyond cough relief and point more to the germ-killing attributes of both foods. In a November 2006 study from the African Journal of Traditional, Complementary, and Alternative Medicine, various bacteria and fungi were inhibited by an extract from the juice and rind of the fruit. A March 2011 study in the Annals of Clinical Microbiology and Microbiology tested plant extracts such as ginger, garlic and lime in E. Coli contaminated water. Only lime inhibited bacterial growth.
An April 2011 review in the Asian Pacific Journal of Tropical Biomedicine found significant scientific support of the antimicrobial properties of honey.
The British Thoracic Society Cough Guideline Group's September 2006 clinical guidelines includes the possibility of citrus fruit and honey as a home remedy for an acute viral cough in an adult.
It is important to note that the studies done have been minimal and limited in their population. Only one study was done on humans, and that was with children. No studies were done on lime in humans. Additional studies supporting honey and lime's antimicrobial properties were not done on people and may not relate to organisms that cause coughs.
For most populations, honey and lime have little to no risk of harm. However, children 2 and under should never be given honey, as there is risk for botulism.
Because of the wide variety of conditions that can cause a cough, including cancer and heart failure, do not attempt to treat a chronic cough on your own. New coughs in children and adults should be monitored for other symptoms, as these can develop into serious conditions as well. If you have green, yellow or bloody mucus, make an appointment with your primary care physician. If your cough produces blood or a coffee-ground substance, comes with high fever or causes problems breathing, seek emergency care.