I have tulsi (holy basil) in a pot that I use to flavour my tea and a Genovese basil (ocimum basilicum) bush I use for salads and pastas. I was happy with my very little herb garden until Krishan Guptaa of Organic India informed me that holy basil — Krishna (purple leaves), Rama (small, green leaves) and Vana (larger, green leaves)--can grow almost two metres high.
I was shattered. My plants are midgets, barely a foot high. The tulsi crop that small farmers grow in their tiny holdings in Bundelkhand and Azamgarh for Organic India — the organic products, tea and herbal medicine company has 3,500acre under Tulsi cultivation--are over 6 feet high. Even the tulsi shrubs Guptaa has planted in his neighbourhood park in Gurgaon’s Block-A of Sushant Lok are a lot higher than people who have started walking and doing pranayam (yogic breathing exercise) at the tulsi park.
So I was relieved when told that in this case, size really doesn’t matter. All you need are ten fresh leaves of tulsi a day to get the herb’s full health benefits, said Dr Marc Cohen, Foundation Professor of Complementary Medicine at RMIT University in Australia. What makes Dr Cohen--who has degrees in western medicine, physiology and psychological medicine and PhDs in Chinese medicine and biomedical engineering--an expert is his massive review of existing peerreviewed scientific studies on tulsi, which are coming out as a book called Herbs and Natural Supplements: an Evidence-Based Guide.
Though research has picked up over the past decade, most studies have been done on animal models. Since I can’t list tulsi’s very many virtues in limited space, I’ve put together a , sample.
Tulsi is a potent adaptogen that lowers cell sensitivity to stress and raises the body’s ability to adapt to changing situations. This means you can chew the herb for practically everything, from anxiety, cough, allergies, asthma, fever, diarrhoea, indigestion and vomiting to heart disease, arthritis and snakebites (Mohan, Amberkar et al 2011). It’s antioxidants content is as high as ginger, garlic, pink grapefruit, red grapes and plums. As in grapes, the anti-oxidant content of dark tulsi is higher than the green ones.
In diabetics, it reduces fasting glucose levels, blood cholesterol and triglycerides (Muralikrishnan, Pillai et al 2013), reduces plasma glucose and HbA1c — the test to measure average level of blood glucose over three months — and lowers diabetesrelated vision damage (retinopathy). It was shown to lower cholesterol in people in a small human trial (Verma, Dubey et al 2012).
It lowers the toxic effects of common pesticides such as endosulfan, and protects against liver toxicity caused by painkillers such as paracetamol and drugs used to treat tuberculosis and cancers. In animal models, extracts lower tumour size and increase cancer survival (Monga, Sharma et al 2011) while lowering radiation-induced damage to cells and DNA (Subramanian, Chinatalwar et al 2005) associated with cancer treatment. Leaf extract protects genetic damage from chromium and mercury poisoning (Babu and Maheshwari 2006).
All varieties are high in Vitamins A and C, zinc, calcium, iron and chlorophyll (Shafqatullah, Khurram et al 2013), which is obvious to anyone who’s made fresh pesto sauce at home. Its anti-inflammatory that lowers infection and water retention (edema). The usolic acid in tulsi lowers anxiety as effectively as drugs like diazepam (Pemminati, Gopalakrishna et al 2011) and depression as well as the tricyclic antidepressant drug, imipramine. The cognitive edge it gives doesn’t end here. It improves working memory, reference memory and spatial memory in not just rat with stress-induced brain impairment (Raghavendra, Maiti et al 2009).
Apart from stress, it increases stamina and fights fatigue. In rodent models, tulsi extract normalised physiological and biochemical changes linked with tiredness and mental stress. Extracts helped rats swim longer and utilise glucose better (Prasad and Khanum, 2012). Other studies have shown it reduces stress-related oxidative damage on the heart, skeletal and brain tissues.
Tulsi is extremely safe even in high doses, with the ratio between the lethal and effective dose being more than 300 (Singh 2010). The only red flag is that its anti-platelet action could theoretically interact with blood-thinning medicines and cause bleeding in surgery, and its strong antidiabetic action may interact with diabetes medication, but no actual cases have been reported.