Skip to content
JournalBotanica home

Botanical Index / everything about

Oat

Finely milled oats for calmer, better‑behaved skin

Avena sativa

A giant spoon pours soft oat powder like snow over someone with itchy skin.
Illustration

The short version

Colloidal oatmeal is whole oat grain milled so fine it stays in water instead of sinking. People put it in baths, cleansers and creams to soothe dryness and itch and to support the skin barrier.

Family
Poaceae
Part used
Grain (finely milled as colloidal oatmeal)
Comes from
Probably the Fertile Crescent; grown across temperate regions

Good for?

Common in moisturizers, washes and bath powders for dry, itchy and sensitive or eczema‑prone skin. It helps skin hold water, feels soothing, and is generally gentle enough for everyday use. You’ll also see oat lipid or kernel extracts in barrier‑care formulas and redness‑care routines.

Does it actually work?

Real trials.

Controlled trials on people back it up.

Evidence grade 4 out of 5.

What the studies say

Modern clinical studies, including randomized and controlled trials, report improvements in eczema signs, hydration, pH and barrier measures with colloidal oatmeal–containing formulations, though many products also include other moisturizing ingredients, making it hard to know how much of the benefit is due to oats alone. An open‑label study of a lotion with oat flour, oat oil and oat extract suggested improved dryness, itch and quality‑of‑life in adults with sensitive skin and mild‑to‑moderate psoriasis. A randomized trial in rosacea found a moisturizer containing oat and aloe reduced redness and lesion counts more than a comparator treatment by weeks 8–12. Lab and model‑skin work shows oat phenolics (avenanthramides) and other fractions can reduce oxidative stress and inflammatory signals, modulate mast cells linked to itch, and upregulate barrier‑related proteins. Overall, evidence is encouraging for soothing and barrier support, with the caveat that many trials use multi‑ingredient formulas or lack strict vehicle controls.

A person soaks in a milky oat bath surrounded by tall oat stalks and a rubber duck.
Illustration

What's inside

  • Present; amount varies with source and processingBeta‑glucan (polysaccharides)Forms a hydrating film; lower‑molecular‑weight oligos can show better skin penetration in models.
  • Present in low amounts; varies by materialAvenanthramides (phenolic amides)Antioxidant and calming activity shown in cells and reconstructed skin.
  • Present; varies by extractLipids (linoleic‑/oleic‑rich)Oat lipid extracts also include ceramides and sterols used for barrier care.
  • Present in lipid extract; levels varyCeramides (in oat lipid extract)Detected and visualized in skin models after topical application.
  • Present; varies with milling and extractionProteins/peptidesContribute to water binding and film forming on skin.
  • Enriched in sprout extracts; variesSteroidal saponins (avenacosides; notable in sprouts)Linked to modulation of epidermal differentiation genes in irritation models.

Read this first

Generally well tolerated in studies. As with any plant extract, contact allergy is possible; people with known oat or cereal allergies or very reactive skin should patch test first or consult a professional.

The stories

1 in the Journal

Evidence Check · Oat

Oat and colloidal oatmeal: the botanical dermatologists actually recommend

Colloidal oatmeal is one of the few botanicals with randomized trials and mechanistic lab work supporting its use for dry, itchy and eczema-prone skin. The strongest evidence is for formulated topical products containing colloidal oat or its extracts; many studies test finished products or combination formulas rather than isolated oat constituents.

  • Skin
  • Body

Reviewed

Sources

  1. Investigation into the delivery and evaluation of a unique Avena sativa (Oat) Lipid Extract on skin barrier using LC‒MS/MS, Raman spectroscopy, immunostaining analysis and skin efficacy. — Gombert E, Dewis C. · International journal of cosmetic science · 2026
  2. Open-Label Study: Over-the-Counter Oat Flour/Oat Oil/ Oat Extract-containing Lotion With Avenanthramides for Sensitive Skin and Psoriasis. — Hubert K, Lisante TA, Nollent V. · Journal of drugs in dermatology : JDD · 2025
  3. Protection of skin from UVB-induced photoaging: Antioxidant and anti-inflammatory effects of avenanthramide C from oat sprout extract via suppression of MAPK pathways. — Ock CW, Her S, Bae ES, Park HJ, Pyee J, Lee SK. · Journal of photochemistry and photobiology. B, Biology · 2026
  4. Oat β-Glucooligosaccharides: Preparation, characterization, skin permeability, and photodamage repair for skincare applications. — Jiang H, Li J, Luo S, Cui C, Luo L, Li Y, Liang Z. · Carbohydrate research · 2025
  5. Oat (Avena sativa L.) Sprouts Restore Skin Barrier Function by Modulating the Expression of the Epidermal Differentiation Complex in Models of Skin Irritation. — Kim HS, Hwang HJ, Seo WD, Do SH. · International journal of molecular sciences · 2023
  6. Inhibitory Effects of Fermented Sprouted Oat Extracts on Oxidative Stress and Melanin Overproduction. — Cho H, Yang J, Kang JY, Kim KE. · Antioxidants (Basel, Switzerland) · 2024
  7. Bacterially Converted Oat Active Ingredients Enhances Antioxidative and Anti-UVB Photoaging Activities. — Lee JK, Kim I, Jeon EK, Ha JH, Hwang CW, Kim JC, Yang WS, Choi H, Kim HD, Kim CH. · Evidence-based complementary and alternative medicine : eCAM · 2022
  8. Efficacy, Tolerance, and Safety of a Novel Botanical Anti-Inflammatory Moisturizer in Rosacea: Results From a Double-Blinded, Randomized Controlled Trial. — Draelos ZD. · Journal of cosmetic dermatology · 2026
  9. ARTICLE: Colloidal Oatmeal Part I: History, Basic Science, Mechanism of Action, and Clinical Efficacy in the Treatment of Atopic Dermatitis. — Allais B, Friedman A. · Journal of drugs in dermatology : JDD · 2020
  10. Colloidal oatmeal formulations and the treatment of atopic dermatitis. — Fowler JF. · Journal of drugs in dermatology : JDD · 2014
  11. Effects of Colloidal Oatmeal Topical Atopic Dermatitis Cream on Skin Microbiome and Skin Barrier Properties. — Capone K, Kirchner F, Klein SL, Tierney NK. · Journal of drugs in dermatology : JDD · 2020
  12. A 1% colloidal oatmeal OTC cream is clinically effective for the management of mild to moderate atopic dermatitis in Black or African American children. — Lisante TA, Kizoulis M, Nuñez C, Hartman CL. · The Journal of dermatological treatment · 2023
  13. The Efficacy of Colloidal Oatmeal Cream 1% as Add-on Therapy in the Management of Chronic Irritant Hand Eczema: A Double-Blind Study. — Sobhan M, Hojati M, Vafaie SY, Ahmadimoghaddam D, Mohammadi Y, Mehrpooya M. · Clinical, cosmetic and investigational dermatology · 2020
  14. 1% Colloidal Oatmeal Cream/Baby Wash Regimen Improved Atopic Dermatitis in Pediatric Patients From First Use. — Kosmoski G, Friscia D, Mack MC, Brooks LM, Cobb CW, Draelos ZD. · Journal of drugs in dermatology : JDD · 2025
  15. Effects of eczema calming lotion on the stratum corneum in atopic dermatitis: Corneodesmosin and intercellular lipid lamellae. — Ilarslan H, Lathrop WF, Dobkowski B, Hawkins SS, Scott J, Bajor J, Mayes AE. · International journal of cosmetic science · 2024
  16. Effects of a Moisturizer Containing Colloidal Oatmeal and Filaggrin Technology on Staphylococcus Species In Vitro. — Whiting C, Abdel Azim S, Joly-Tonetti N, Lachmann N, Friedman A. · Journal of drugs in dermatology : JDD · 2025