Turmeric

What it is

Turmeric is the bright orange root of Curcuma longa, a ginger relative used for thousands of years in South Asian cooking, ceremony and medicine. Its best-studied compound, curcumin, makes up a few percent of the dried root and has clear anti-inflammatory and antioxidant activity in the laboratory. Curcumin is poorly absorbed from the gut, which is why many supplements add black pepper extract or use special formulations¹.

What the evidence says

Evidence: limited. Eighteen small human studies, oral and topical, point in a hopeful direction, but they are short, mixed in quality and rarely repeated.

A 2016 systematic review found 18 human studies of turmeric or curcumin for skin conditions including acne, psoriasis, eczema and radiation dermatitis: nine oral, eight topical and one both. Ten reported a significant improvement in disease severity over controls, and the reviewers described the evidence as early and limited². The strongest single trial is in radiation dermatitis: 30 women having breast radiotherapy took 6 g of oral curcumin a day, and fewer developed severe skin breakdown (29% against 88% on placebo)³. That is a specialist, supervised setting, not something to copy at home.

For everyday concerns such as spots, redness or dark marks, the studies are small, short and often use turmeric alongside other ingredients, so it is impossible to say what the turmeric contributed. Home masks of turmeric powder have never been properly tested. The anti-inflammatory idea is reasonable; the proof is not there yet.

How people use it

• In a wash-off mask: a quarter teaspoon of turmeric in a tablespoon of plain yoghurt or honey, left on for 10 minutes, once a week. Expect a yellow tinge for a few hours.
• In a formulated cream or serum: products list "Curcuma longa extract" or tetrahydrocurcumin, a colourless derivative that avoids staining.
• In food: cooking with turmeric is safe and pleasant for almost everyone; it is not a skin treatment.

Cautions

• Turmeric stains skin, nails, fabric and grout yellow; the colour fades from skin within a day or two.
• It can cause allergic contact dermatitis, reported from turmeric-based cosmetics and traditional kumkum powder⁴. Patch test, and stop if the skin reddens or itches¹.
• Oral supplements can cause nausea, reflux and diarrhoea, and liver injury has been reported with high-absorption curcumin products¹.
• Supplements may be unsafe in pregnancy, and herbal products can interact with medicines, so talk to a pharmacist or doctor before taking them¹.
• A yellow mask is not a treatment for inflamed or scarring acne; see our natural acne care guide and DIY remedies to avoid.