The Benefits of Neem – Ancient Application to Modern Use
Lisa Murray, RDN, LD
Neem (Azadirachta indica) is a large evergreen tree endemic to the Indian subcontinent, which is prized for its medicinal value. Introduced to many areas in the tropics, the neem tree has been a mainstay in Ayurvedic, Siddha, and Unani medicine for thousands of years.
Every part of the tree—its roots, bark, resin, gum, twigs, leaves, seeds, flowers and fruit—contain chemical compounds with extensive therapeutic qualities, including antimicrobial (antiviral, antifungal, antibacterial), anti-inflammatory, antihelminthic, immunomodulatory, hepato-nephro-neuro protective and even anticancer properties.
Traditionally, slender neem twigs (called datun) are chewed as a toothbrush and then used as a tongue cleaner, which has been a daily practice in India, Africa and the Middle East for centuries. Most of India’s rural population still start their day with the chewing stick, while in urban areas neem toothpaste is preferred. Neem twigs are still collected and sold in markets for this use and in rural India one often sees youngsters in the streets chewing on neem twigs. It has been found to be as effective as a toothbrush in reducing plaque and gingival inflammation.
Neem leaf extract is a potent antioxidant used internally as an antimicrobial as well as an anti-inflammatory and antipyretic. There are many studies evaluating its use as a cancer preventive.
Neem oil (or neem seed oil) is cold pressed or extracted from the seeds of the olive-like fruit. It is a thick oil which can vary in color; it can be golden yellow, yellowish brown, reddish brown, dark brown, greenish brown or bright red. It has a strong and somewhat unpleasant odor. Neem oil is antibacterial, antifungal and antiviral as well as anti-inflammatory and antioxidant. It is composed mainly of triglycerides and contains many triterpenoid compounds. Because it is a natural substance, the composition varies, though it is usually between 25-55% oleic acid, which is an omega-9 fatty acid, and between 6-16% linoleic acid, which is an omega-6. Research suggests that the high fatty acid content may be responsible for its effectiveness in treating skin disorders. Eighty percent of India’s supply of neem oil is used by neem oil soap manufacturers (soaps can be made with up to 40% neem oil). Not only antimicrobial, it’s also very soothing and moisturizing.
Neem oil has a wide spectrum of preventive and curative uses. It can be applied topically to fungal and bacterial skin infections as well as used to heal skin disorders of every type. Neem may have a positive effect on chronic skin conditions that have not been successfully helped through conventional medical treatments. Acne, dry skin, dandruff, psoriasis, eczema, herpes and ringworm have all been shown to respond to neem oil salves and lotions. Because Ayurveda is a health practice which stresses prevention as much as treatment, neem oil is also incorporated into soaps, shampoos for maintaining healthy scalp and hair, balms, creams, cosmetics and oral hygiene products like toothpaste (due to its potent antimicrobial properties). Neem oil is an insecticide and insect repellant, useful in shampoo and body care products to repel fleas, lice and mites for both people and pets, which is very important in tropical climates where pests thrive.
Neem extracts and neem oil have been found to prevent implantation and may even have an abortifacient effect.  Neem oil has traditional use in India as a spermicide. Neem oil and other neem products, such as neem leaf extract, capsules, and tea, should not be consumed by pregnant women, women trying to conceive or children. Internal use of neem seed oil can be potentially toxic and should not be used internally in large doses or for long periods of time. In India, where Neem oil is widely used, there are case reports of neem oil poisoning in infants who were a given single doses of Neem oil (few drops to 5 ml) as well as adults presenting with features of toxic encephalopathy, metabolic acidosis, and hepatic toxicity.  Both infants and adults recovered completely with supportive treatment. Sundaravalli et al., in a case series of 12 children with neem oil poisoning, who were given a single dose of Neem oil (25-60 ml), reported fatality in 10 cases with features of toxic encephalopathy and metabolic acidosis.3 In adults, short-term use of neem oil in minute quantities is safe, but high doses may cause toxic encephalopathy.
The bottom line is that Neem provides extremely useful, safe and versatile plant medicine. However, it is also very potent and it’s important that practitioners know and understand what part of the plant they are using and how to properly use it.
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Published online 2016 March 1. doi: 10.1155/2016/7382506
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