How we research, test and correct these guides
Short answer
Every guide and tool here follows four rules: claims trace to a named source, tools publish their method, we say what we do not know, and corrections are dated. This page explains the standard, the limits of it, and how to challenge it.
The four rules
- A source, a measurement, or nothing. Any claim about skin, hygiene, infection risk or bacterial load cites a named study, dermatology body or health service, with a link. If a number exists, we say where it came from and what it does not cover. Where no source exists and no measurement is possible, we do not publish the claim.
- Tools publish their method. The cleaning schedule calculator lists its inputs, its base intervals, every multiplier it applies, and where each base interval came from. You should be able to read the method and disagree with the arithmetic rather than the conclusion.
- We state the limits out loud. Each page carries a callout naming what the evidence does not support. If the research measures bacterial contamination but not acne outcomes, the page says so rather than borrowing the authority of the word "bacteria".
- Corrections are dated. When we fix something substantive, the change and its date go on the page.
What we will not do
| Not this | Why |
|---|---|
| Invent statistics, or attribute them vaguely ("studies show") | It is the fastest way to lose a reader and a search engine at once, and it is the reason most brush-cleaning advice online contradicts itself |
| Publish fake reviews or invented review counts | This is a shop. If we are going to sell you a brush set, the least we owe you is not making up what other people said about it |
| Hide the commercial relationship | We sell the tools these guides discuss, so guides recommend the right tool for the job even when it is the cheaper one, and say when a product is unnecessary |
| Present cleaning as an acne cure | The NHS lists dirty skin and poor hygiene as a myth about acne causes. Cleaning is hygiene and performance, and our pages say exactly that |
| Copy a competitor guide and reword it | Every guide here is built from the primary sources and our own tool output |
| Give medical advice | We explain hygiene, materials and safe use. Diagnosis and treatment belong to a clinician |
How a guide gets written here
- We start from the question people actually search, using real query and search-result data rather than a guessed content plan.
- We pull the primary sources on that question: dermatology body guidance, health service guidance, peer-reviewed studies on contamination and tool hygiene, and manufacturer or craft references for material behaviour.
- Where a decision depends on a number, we build a tool rather than describing the number in prose. The cleaning schedule calculator exists because "how often" has no single answer.
- We write the shortest version that answers the question, then add only the detail that changes a decision. If a paragraph does not change what you do, it gets cut.
- Before publishing, a second pass looks for overclaiming. Any sentence that asserts more than its cited source supports is cut or softened. That is why our pages say "no controlled trial shows this" instead of implying one exists.
Where our brush guidance comes from
| What we claim | Where it comes from |
|---|---|
| Wash brushes every 7 to 10 days, rinse only the tips, dry flat, never share | American Academy of Dermatology, how to clean your makeup brushes |
| Wet-product brushes weekly, eye brushes about fortnightly, dry-powder brushes up to monthly | Cleveland Clinic (Melissa Piliang, MD) |
| Acne is not caused by dirty skin or poor hygiene | NHS, acne causes |
| Used brushes carry bacteria, including Staphylococcus and Pseudomonas species | Attar and Imam, International Journal of Microbiology, 2025 |
| Used cosmetics and applicators are frequently contaminated, with high loads in blenders | Bashir and Lambert, Journal of Applied Microbiology, 2020 |
| Natural hair has a cuticle and grips powder; synthetic fibre does not and suits cream and liquid | Hair and Makeup Artist Handbook, makeup brush construction |
Corrections and contact
If a page here is wrong, out of date, or cites something that has since changed, tell us through the contact page and we will fix it and note the date.
On conflicts of interestWe sell brushes, storage and care tools. That is a real conflict, and the honest answer is disclosure rather than denial. Practical consequences: our pages tell you that a five-brush set covers what a twelve-piece set covers, that dish soap can stand in for a brush cleanser, and that a worn-out brush should be replaced rather than rescued with more product.
Start here
Sources
- American Academy of Dermatology. How to clean your makeup brushes — www.aad.org/public/everyday-care/skin-care-secrets/routine/clean-your-makeup-brushes
- Cleveland Clinic (Melissa Piliang, MD). How to clean your makeup brushes and why you need to — health.clevelandclinic.org/cleaning-makeup-brushes
- NHS. Acne: causes (including the myth that acne is caused by dirty skin and poor hygiene) — www.nhs.uk/conditions/acne/causes/
- Attar RMS, Imam MA. Assessing the levels and types of bacterial contamination in cosmetic brushes: implications for beauty and hygiene in Jeddah City. International Journal of Microbiology, 2025 — pmc.ncbi.nlm.nih.gov/articles/PMC12074853/
- Bashir A, Lambert P. Microbiological study of used cosmetic products: highlighting possible impact on consumer health. Journal of Applied Microbiology 128(2):598-605, 2020 — doi.org/10.1111/jam.14479
- Hair and Makeup Artist Handbook. A guide to makeup brush construction (bristle types, cuticle structure, ferrule and glue) — hair-and-makeup-artist.com/makeup-brush-construction/