Allium Cepa Bulb Extract

INCI: ALLIUM CEPA BULB EXTRACT

Also known as: Allium Cepa Bulb Extract

A plant extract with antioxidant compounds that may help soothe and condition the skin

At a glance

Reduces Irritation Reduces Redness Good for Scar Healing

Best For Skin Types

All, Sensitive, Combination

Addresses

Redness, Sensitivity, Irritation

Usage Frequency

Daily

What Is Allium Cepa Bulb Extract?

Allium cepa bulb extract is derived from onion bulbs and contains bioactive compounds including polyphenols and quercetin flavonoids. These are naturally occurring antioxidants that onions produce as part of their defensive chemistry.

In skincare formulations, this extract functions as a skin conditioning agent. The antioxidant profile suggests it may help protect skin from oxidative stress, though the specific mechanisms by which these compounds benefit skin remain an area of ongoing research.

How It Works

Onion bulbs contain sulphur-based compounds and flavonoid antioxidants that form when cells are damaged or processed. These bioactive molecules can help reduce oxidative stress — an imbalance of free radicals that contributes to skin ageing and inflammation.

When applied topically in extract form, these compounds may help condition the skin barrier and provide antioxidant protection. However, the bioavailability of these compounds when applied to skin (rather than ingested) is not yet well established through clinical research.

Clinical Evidence & References

Research has confirmed that onion bulb extracts contain significant levels of polyphenols and quercetin with measurable antioxidant activity in laboratory assays. Studies have also explored how these flavonoids are metabolised when absorbed systemically, suggesting they remain bioactive in the body.

Evidence for topical skincare benefits is more limited. Whilst traditional use and antioxidant chemistry are promising, well-designed clinical trials specifically examining this ingredient's effects on skin conditions — particularly for redness, irritation, or scar appearance — remain sparse. Further research would strengthen understanding of its practical efficacy in skincare products.

How to Use

Allium cepa bulb extract is typically found in concentrations below 0.1% in skincare products, often as one of several soothing or conditioning agents. Use as directed on your product; there is no specific guidance for optimising results beyond consistent application. If combining with other actives, observe your skin's response.

Safety & Precautions

Onion extract is generally well-tolerated in skincare. Those with known onion sensitivity or allergy should avoid products containing this ingredient.

How widely it's used

0.1%
of skincare products contain this ingredient — placing it in the top 50% of most-used ingredients.
Most common in: Treatments Moisturisers Cleansers

Regulatory information

Standardised cosmetic-ingredient identifiers used by regulators.

Show identifiers
INCI Name
ALLIUM CEPA BULB EXTRACT
EC Number
232-498-2
Function
Skin Conditioning

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