Scrolling through social media, it's hard to miss influencers raiding the pantry for "natural" beauty fixes: baking-soda scrubs, garlic spot sticks, cayenne masks that promise to tighten pores and banish dullness.
Author
- Adam Taylor
Professor of Anatomy, Lancaster University
The appeal is obvious. Why pay for a dermatologist-tested cream when everyday ingredients come with antimicrobial or exfoliating properties? Yet what looks sensible in a 30-second reel can translate into painful, sometimes dangerous, DIY disasters.
Just because it's edible doesn't mean it's safe to put on your skin.
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Garlic, chilli, turmeric and their spice-rack neighbours may contain potent bioactive compounds, but in raw form they are unrefined, unstable and frequently far too harsh for the delicate acid mantle that shields human skin .
Professional cosmetic chemists isolate biologically active plant compounds, purify them and blend them at precisely calibrated doses suited to the skin's natural pH. A spoonful of cayenne or a pinch of bicarbonate of soda offers none of that control. Slapping pantry powders on your face risks chemical burns, rashes or long-term damage.
Concentration is the first stumbling block. A teaspoon of baking soda, for instance, has nothing in common with a safety-tested cleanser that might contain less than 1% sodium bicarbonate balanced by humectants (moisture-attracting ingerdients) and acids.
Likewise, a swipe of raw cayenne delivers an unpredictable hit of capsaicin, the fiery molecule that dermatologists use in nerve-pain creams, but only at strictly managed strengths.
Pure kitchen spices also arrive with their own microorganisms: they are agricultural products processed in bulk. Once mixed with water or oil to create a mask they can become bacterial broths, inviting infection rather than a healthy glow.
Baking soda: more alkaline than your skin can handle
Baking soda illustrates how quickly a "harmless" staple can upset skin chemistry. Celebrated online for mild antibacterial and antifungal properties, sodium bicarbonate is, in fact, highly alkaline.
Normal skin sits in the acidic range of 4.5 to 5.5. Apply a thick alkaline paste and the pH shoots upward, disrupting friendly microbes and triggering irritation and breakouts.
Studies in humans show a bicarbonate paste does not relieve psoriasis itch or redness. On babies, baking-soda soaks for nappy rash have caused hypokalaemic metabolic alkalosis (low potassium levels in the blood), leading to seizures and coma.
Some influencers say that the same paste that soothes burns is safe, but it can be dangerous. There are reports of baking soda causing severe skin damage - such as deep burns and even tissue death - when it was applied to broken or injured skin.
Even more alarming are posts touting it as a DIY cancer therapy, on the theory that it "neutralises" tumour acidity. High oral doses have disrupted heart rhythm and caused death .
Garlic: ancient remedy, modern irritant
Garlic's folklore as a "natural antibiotic" fares no better. Raw cloves are loaded with sulphur compounds that behave like caustic chemicals. Direct application has produced allergic or irritant dermatitis and even third-degree burns on lips and eyelids.
Any scars may outlast the pimple they were supposed to heal.
Research on allicin, a natural compound in garlic, shows promise as an antimicrobial and heart-protective agent - potentially helping to lower blood pressure, reduce inflammation and prevent heart disease. But that study used purified extracts in lab conditions - not a clove rubbed straight onto skin.
Chilli peppers: capsaicin isn't a beauty hack
Chillies present an even hotter hazard. Capsaicin is licensed for nerve-pain creams yet even pharmacists warn of burning, redness and swelling. Home kitchens, obviously, lack a pharmacist.
Cooks who handle chillies daily can develop Hunan hand , an intensely painful, burning dermatitis. Despite this, some beauty hacks still recommend cayenne masks for radiance. Airborne or topical capsaicin stings the eyes, triggering involuntary spasms and long exposure can cause lasting corneal injury .
Inhaling the dust provokes coughing fits and, over time, lung inflammation . Because capsaicin penetrates the skin , repeated use can damage peripheral nerve fibres - dulling your ability to feel heat or pain - and disrupt normal blood flow , which may lead to tissue irritation, delayed healing or increased sensitivity. It can also affect blood pressure , especially in people with underlying health issues.
A notorious example underscored the danger: a woman suffered agonising vaginal burns after unknowingly using a tampon contaminated with pepper spray that had leaked in her handbag. Even mustard powder can deliver second-degree burns when misapplied.
Spice rack roulette: staining, burning, dermatitis
Spices thought to be milder are hardly innocent. Cinnamon is a trendy lip-plumper, yet dermatologists document contact dermatitis and chemical burns . Ginger "glow" masks leave many users with red, irritated skin .
Clove oil, hyped as a spot cure, has produced caustic injuries . Saffron can cause allergic rashes , while turmeric's curcumin, celebrated online for anti-inflammatory benefits, often delivers dermatitis and bright yellow staining that lingers for days.
Dermatologists recommend patch-testing any new skincare product, even "pure" essential oils , on the inner arm for 48 hours.
Powdered spices also wander: a cinnamon scrub can fill the air with irritant dust that settles in eyes or airways, leaving you sneezing and sore instead of glowing.
Respect your barrier
Dermatologists emphasise the importance of protecting the skin barrier: gentle, pH-balanced cleansers and moisturisers help maintain the acid mantle that defends against germs. Your doctor or pharmacist can guide you toward proven plant-based ingredients like niacinamide , aloe vera , or colloidal oatmeal , all of which offer skin benefits without the sting.
Next time an influencer urges you to "ditch chemicals" or promote "clean beauty" and scoop your skincare out of a spice jar, remember, everything is a chemical. Some belong on your dinner plate - very few belong on your face.
Adam Taylor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
