Know what you're putting in your body.

158 herbs, nutrients, and compounds. What the science says, what tradition knew, and what to watch for. Founding members keep this running.

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SKIN BARRIER & MOISTURE

Neem

Azadirachta indica

also known as neem leaf, neem oil

Moderate (topical) / weak (internal)

A fast-growing Indian tree called 'the village pharmacy' in much of South Asia, where every part — leaves, bark, seeds, oil — has a documented traditional use. Modern research backs the topical antimicrobial and pesticidal claims most strongly. Internal use has a longer traditional history but a more cautious safety picture.

Topical neem oil is associated with skin and scalp support — eczema, acne, dandruff, head lice
Antimicrobial and antifungal action documented in lab studies and traditional use
Long traditional use for oral health — neem twigs are still used as toothbrushes in parts of India
Natural insecticide — neem-based products are used in organic agriculture
Traditional internal use for blood sugar, parasites, and inflammation
Active in laboratory studies against many bacteria, fungi, viruses, and parasites

Neem oil should never be ingested — it has caused serious toxicity, including in children given it as a folk remedy

Internal use of neem leaf or extract has caused liver injury in some reports

Skip during pregnancy — neem has been associated with miscarriage and is sometimes used traditionally as a contraceptive

Skip during nursing

Skip in young children for any internal use

Use caution with diabetes medication — neem may lower blood sugar

Use caution with autoimmune conditions — neem affects immune signaling

Stop two weeks before surgery

Memorial Sloan Kettering About Herbs · EMA Herbal Medicinal Product Monographs · American Botanical Council HerbMedPro · Memorial Sloan Kettering About Herbs · EMA Herbal Medicinal Product Monographs · American Botanical Council HerbMedPro

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