On The Shelf
Mickie Cathers
Tulsi, the holy basil, is a supplement commonly sold as a tea and advertised as a way to boost a healthier immune system, relieve stress, and promote relaxation. Can this aromatic, perennial herb native to Southeast Asia provide overall relief?
Background
Tulsi (Ocimum tenuiflorum) has a long history of use in Ayurvedic medicine and has been referred to as the “queen of herbs,” and the “elixir of life.” All parts of the plant, including leaves, flowers, and seeds have been used in treatments for a multitude of health conditions including bronchitis, rheumatism, pyrexia, epilepsy, asthma, eye and skin diseases, headache, wounds, inflammation, earache, malaria, stomach ulcers, insect bites, and more. Though tulsi is also known as holy basil, it is very different from the sweet basil used in pesto or Thai basil commonly found in pho and other Southeast Asian dishes.
Is there a benefit?
Tulsi is high in vitamins A and C, calcium, zinc, iron, and chlorophyll. As an essential oil, it contains a rich source of bioactive compounds such as camphor, eucalyptol, eugenol, a-bisabolene, b-bisabolene, and b-caryophyllene thought to be responsible for tulsi’s antimicrobial properties. The leaves’ major component, eugenol (a powerful anti-inflammatory and antioxidant)—also found in cinnamon and cloves—assists in triggering cell death and cell cycle arrest, and inhibiting migration, metastasis, and angiogenesis in a number of cancers, thereby reducing the growth of tumors.
Clinical trials investigating the beneficial effects of tulsi in humans are increasing and have focused on its possible benefits in a wide variety of conditions and diseases through its antioxidant properties.
A March 16, 2017, systematic review published in Evidence-Based Complementary and Alternative Medicine evaluated 24 clinical studies on tulsi’s therapeutic effects related to metabolic-related disorders, cardiovascular disease, immunity, and neurocognitive function.
Jamshidi and Cohen concluded that the findings from these studies showed significant improvements in metabolic disorders such as T2D; immune system and viral infections; and cognitive function, mood, and stress. The authors suggested that tulsi may assist in alleviating stress and normalizing blood glucose levels, BP, and lipid profiles. However, further clinical evaluation is recommended.
A randomized, double-blind, placebo-controlled trial published in Frontiers in Nutrition on September 2, 2022, investigated the effects of a tulsi extract on stress, mood, and sleep in adults experiencing stress. For 8 weeks, volunteers aged 18 to 65 years old received either 125 mg of tulsi extracts twice daily or a placebo. Lopresti and colleagues measured outcomes using standardized stress scales as well as a between-group differences in cortisol. Data from a wrist-worn fitness and activity tracker was assessed to evaluate sleep quality.
Results revealed that tulsi supplementation was associated with greater improvements in all scores and no adverse events were reported. The authors concluded that 8 weeks of tulsi extract supplementation may reduce objective and subjective measures of stress and improve sleep quality.
Dosage and availability
Tulsi is available online and in health food and grocery stores as tea, liquid extract, powder, pills, and capsules. The suggested dosage ranges from 300 mg to 2,000 mg per day.
What to tell your patients
Tulsi is generally considered safe with no adverse effects reported in clinical trials. Advise patients that tulsi may lower blood glucose levels and to avoid tulsi if lactating, pregnant, or trying to conceive as there is not enough research to recommend use. As with all supplements, FDA doesn’t monitor safety or effectiveness. ■