Basil Common name: Common basil, sweet basil Botanical name: Ocimum basilicum Skip to: Botany Helpful for Traditional use How it works Amount to take Side effects & interactions References Parts used and where grown The leaves of basil and its many close relatives are used as medicine. The seeds are also used medicinally in India and Southeast Asia. Though it originates on the shores of the Mediterranean Sea and the Middle East, common basil now grows in gardens all over the world. Three important relatives with similar properties are Ocimum canum (hairy basil), O. gratissimum (basil), and O. sanctum (holy basil). Basil has been used in connection with the following conditions (refer to the individual health concern for complete information): Health Concerns Constipation Diabetes Indigestion Historical or traditional use (may or may not be supported by scientific studies) Basil has been a culinary herb in Europe and Central Asia since before the written word. In India the seeds were used for diarrhea, mucous discharges, constipation, and as a general demulcent (soothes mucous membranes); the leaves were used for indigestion and skin diseases. In traditional Thai herbalism, the plant is used for coughs, skin diseases, and intestinal problems. The seed is used as a bulk-forming laxative and diuretic. Active constituents Basil contains a strong-scented volatile oil composed primarily of terpenoids, particularly eugenol, thymol, and estragole. Basil also has what are known as chemotypes, minor variations among plants that contain significantly different mixes of constituents. The exact components of basil oil vary widely, being affected not only by these chemotypes but also by factors such as the time of day of harvest. This may account for some of the variability in scientific research and reports of medicinal efficacy of basil from culture to culture. Preliminary studies on holy basil and hairy basil have shown that the leaf and seed may help people with type 2 diabetes control their blood sugar levels. While the action-mechanism of the leaf is not understood, the seed may work by providing dietary fiber, which helps prevent rapid blood sugar elevations after meals. In addition, the seed has been found to relieve constipation by acting as a bulk-forming laxative in one uncontrolled human study. A similar study showed the seeds useful in elderly people who experienced constipation after undergoing major surgery. The volatile oil of basil has shown antibacterial, antifungal, and antiviral activity in test tube studies. It is also believed to act as a carminative, relieving intestinal gas, and as a mild diuretic, though these actions have yet to be definitively proven. How much is usually taken? A tea can be made by steeping 1 teaspoon of basil leaves in one cup of water for ten minutes. Three cups of this tea can be drunk per day. Capsules of basil can be taken in the amount of 2.5 grams per day. The volatile oil can be taken internally in the amount of 2 to 5 drops three times per day. Are there any side effects or interactions? Although concerns have been raised about the possible cancer-causing effects of estragole, a component found in variable amounts in basil volatile oil, small amounts of basil would not seem to pose a significant threat. However, because some herbal books suggest that estragole may be potentially carcinogenic and has been thought to stimulate uterine contractions, some herbal experts feel it may be best for pregnant or breast-feeding women to avoid use of the herb, especially the volatile oil. People with serious kidney or liver damage should not use basil volatile oil internally, as they could theoretically have trouble eliminating it from their bodies. However, use of basil as a seasoning in food is unlikely to be of concern.