What Is Ectoin? A Protective Molecule from Extremophile Bacteria
Other names: Ectoine
Ectoin is a small molecule produced by bacteria living in harsh environments such as salt lakes to protect themselves. It interacts strongly with water and is used in cosmetics for moisture and barrier support. Most data come from atopic dermatitis creams at 5,5-7%; expectations from an ordinary cream should be more modest.
At a glance
- INCI name
- Ectoin
- Type
- Small cyclic amino acid derivative, extremolyte
- Source
- Bacteria from saline environments; biotechnological production
- Concentrations studied
- 1-2% in cosmetic studies, 5,5-7% in atopic dermatitis creams
- What it does
- Moisture retention, reduced water loss, support for dry and reactive skin
- Evidence level
- Small studies, largely linked to the manufacturer
What's on this page?
Salt lakes, drought and intense radiation are conditions that are lethal for most living things. Some micro-organisms living there accumulate small molecules called extremolytes to protect their cells. Ectoin is one of these. Chemically it is a cyclic amino acid derivative, and the cosmetics sector has borrowed it for its property of protecting proteins and cell membranes against dryness.
What does ectoin do in the skin?
The proposed mechanism is that ectoin forms a water shell around proteins and membranes. In computer simulations, ectoin-water clusters remained stable for longer at high temperature than glycerin-water clusters. In measurements with an oil-in-water emulsion, transepidermal water loss changed in favour of the barrier. Cell experiments showed it reduces stress signals triggered by UVA and mitochondrial DNA damage. The authors of these basic studies worked for the company that developed ectoin, so independent replication is needed.
How strong is the evidence for ectoin?
A peer-reviewed systematic review found only six clinical studies. Five were on atopic dermatitis and one on retinoid dermatitis. The authors report positive results for dryness and itching, but acknowledge that the certainty of some studies is low. One of the authors is an employee of the manufacturing company.
| Study | Product | Result |
|---|---|---|
| 104 healthy women, placebo-controlled | 2% emulsion | Moisture and ageing measurements improved; no side effects reported |
| 65 adults with atopic dermatitis, double-blind, 4 weeks | 7% cream, against a steroid-free reference cream | Effect similar, i.e. equivalence rather than superiority |
| Atopic dermatitis, aged 2-18, 70 children, 4 weeks | 1% ectoin and 0,1% hyaluronic acid | Severity score fell more than with the carrier; mild side effects 23,5% versus 5,7% |
| 76 young people taking isotretinoin, 6 months | 7% cream, compared with a dexpanthenol cream | Dermatitis 31,3% versus 53,5%; the study is not blinded |
What can you expect from an ordinary ectoin cream?
The most studied 5,5-7% range belongs to creams developed for atopic dermatitis. Do not expect the same result from the ectoin in a moisturiser whose concentration is not stated. In dry or easily reactive skin it can be seen as a supporting ingredient; it does not replace an eczema treatment. If your disease is flaring, see your doctor; if children or pregnancy are involved, choose the product together with your doctor.
In the review, the most common side effects were burning, tingling and redness, most of which appeared at first application and passed. 455 people using ectoin, 7 of them stopped due to side effects. Still, do not apply it straight to the face: try it for 7-10 days, twice a day, on the inner arm or elbow crease. The EU cosmetics regulation's restricted substances annexes have no separate record for ectoin.
This page is for general information only and does not replace medical diagnosis or treatment. If you have an ongoing skin or scalp problem, consult a dermatologist.