Henna (Lawsonia inermis) is a small flowering shrub native to the hot, semi-arid regions of the Middle East, South Asia, and North Africa. Its leaves contain lawsone, a potent reddish-orange pigment molecule that has made henna the world's oldest and most widely used natural dye for hair and skin. Beyond its cosmetic fame, henna has an extensive medicinal history in Persian, Unani, and Ayurvedic traditions spanning over 5,000 years.

Lawsone, the star active compound, binds to keratin proteins in hair and skin, creating the characteristic stain and also contributing antimicrobial and anti-inflammatory effects on the scalp and skin surface. The rich tannin and flavonoid content gives henna astringent, antioxidant, and wound-healing properties, while gallic acid helps fight bacteria and fungi that cause common scalp and skin problems. Internally, henna's bioactive compounds are thought to support liver function, reduce oxidative stress, and help regulate inflammation throughout the body.

Henna leaf powder mixed into a paste is the most traditional and widely used form, applied topically to hair, scalp, or skin. Decoctions (leaf tea or rinse) are used for wound care and fever in traditional medicine. Standardized capsules or extracts containing lawsone are available for internal use, though these are less studied than topical applications.

• Hair loss and thinning hair
• Scalp dandruff and fungal issues
• Premature graying
• Skin wounds and minor burns
• Skin infections and rashes
• Fever and heat-related illness
• Nail fungus
• Joint pain and inflammation
• Liver support
• Headache (topical use)

• Scalp fungal overgrowth with regular use as a hair treatment
• Secondary skin infection in minor wounds when applied topically

Henna leaf is not found in food — it is a medicinal and cosmetic botanical used as a paste, powder, or decoction. To support the same anti-inflammatory and antioxidant pathways that henna's active compounds work on, prioritize these foods in your diet: (1) Pomegranate — rich in ellagitannins closely related to henna's tannin compounds, strong antioxidant and antimicrobial support; (2) Green tea — high in gallic acid, mirroring one of henna's key active compounds, supports skin and liver health; (3) Turmeric — overlapping anti-inflammatory and liver-supportive pathways; (4) Berries (blueberries, blackberries) — flavonoid-rich, supporting the same antioxidant and anti-inflammatory benefits; (5) Walnuts — provide naphthoquinone-related compounds (juglone) from the same chemical family as lawsone, the primary henna pigment. Avoid excessive alcohol and processed foods, which increase liver oxidative stress and counteract henna's hepatoprotective potential.

• Allergic contact dermatitis (topical) — rare with pure henna, much more common with PPD-adulterated black henna
• Hemolytic anemia — serious risk in those with G6PD deficiency, even via topical absorption
• Scalp or skin dryness with overuse (henna is astringent and can be drying)
• Temporary reddish staining of skin, nails, and fabrics
• Nausea or stomach upset with internal leaf preparations
• Burning or itching sensation if applied to broken or highly sensitive skin
• Not recommended internally during pregnancy — traditional texts flag uterine-stimulating potential

• Recommended daily: Topical hair/scalp paste: 50-100g of henna powder mixed with water, lemon juice, or tea, applied for 1-3 hours before rinsing. Topical wound/skin application: thin paste applied 1-2x daily as needed. Internal decoction (traditional Unani dose): 3-5g dried leaf powder steeped in 200ml water, 1x daily — use only under practitioner guidance. Standardized extract capsules: follow manufacturer guidance, typically 250-500mg once daily.
• Best time of day: Hair treatments: morning or afternoon to allow full drying time. Internal preparations: traditionally taken after meals to reduce stomach upset.
• With or without food: Internal preparations should be taken with food to minimize any gastrointestinal irritation.
• Time to effect: Hair and scalp benefits: noticeable after 2-3 applications over 2-4 weeks. Wound and skin effects: 3-7 days of consistent topical use. Internal benefits: 3-6 weeks of consistent use.
• How long to take it: Topical hair use can be continued indefinitely — monthly or bi-monthly applications are traditional. For internal medicinal use, limit to 4-6 week courses unless under practitioner guidance. Not recommended long-term internally without professional supervision.