“Clean”, “natural”, “green”: marketing words vs what the science says

Walk down any skin care aisle and the words jump out: clean, natural, green, non-toxic, chemical-free. They sound like categories, as if someone had checked. Nobody has. These are marketing terms, and the science behind what’s actually good for your skin doesn’t line up with them very well. Here’s how to see past the words.

None of these words is defined in law

Start with the simple fact. In Canada, no regulation defines “clean”, “natural” or “green” for cosmetics. Health Canada’s rule is general: claims on a label or in an ad must be accurate so they don’t mislead people, and if the Minister of Health suspects a claim is false, the company can be asked for proof. That’s it. There’s no list of what counts as natural and no threshold for how much of the formula has to qualify.

The United States is the same. The FDA says the term “organic” isn’t defined in the laws it enforces (a separate agriculture department program certifies organic farming), and a 2019 editorial in JAMA Dermatology, a leading dermatology journal, put it bluntly: the FDA has failed to define “clean” and “natural”, leaving retailers, bloggers and celebrities to define clean beauty for themselves.

So when two products both say “natural”, the word can mean “made from plant extracts”, “contains one plant extract”, “free of a list we chose” or nothing at all. Each brand writes its own definition, and none of them has to show it to you.

Natural ingredients can be allergens

The most common assumption behind “natural” is “gentle”. Dermatology says otherwise.

Allergic contact dermatitis is an itchy, red, sometimes blistering rash that shows up a day or two after your skin touches something your immune system has learned to react to. The JAMA Dermatology editorial notes that many so-called natural products contain high concentrations of botanical extracts, and that these extracts are a leading cause of both irritant and allergic contact dermatitis.

Essential oils are the clearest example. DermNet, a dermatology reference used by clinicians, lists tea tree, ylang-ylang, lemongrass, sandalwood, clove, jasmine and narcissus oils among the ones that frequently trigger reactions. Each oil can contain more than a hundred different constituents, which is why people allergic to one often react to several. The allergen is sometimes an oxidized component, meaning the oil became more reactive after sitting open to the air. That’s why a bottle you’ve had for months can cause trouble when a fresh one didn’t.

The FDA makes the same point about organic ingredients: an ingredient’s source does not determine its safety, and many plants, organically grown or not, contain substances that are toxic or allergenic. Health Canada’s own labelling page adds that there are no non-allergenic cosmetics. Natural is a description of origin, not of how your skin will respond.

Synthetic ingredients can be safe

The flip side of “natural is gentle” is “chemicals are harmful”. Everything is a chemical, including water and the oils in your skin, so the word is doing no work. The question is always which substance, at what amount, on which skin.

The JAMA Dermatology editorial went through the ingredients most often blacklisted by the clean beauty movement. It reports that the Cosmetic Ingredient Review, an independent expert panel that assesses cosmetic ingredient safety, found propylene glycol, parabens, sulfates and many other demonized ingredients to be non-toxic and non-carcinogenic. Parabens, a group of preservatives, were even named “non-allergen of the year” for 2019 by the American Contact Dermatitis Society, because their rate of causing allergy in patch tests was very low, in the range of half a percent to about one and a half percent.

That doesn’t mean every synthetic ingredient is fine for every person. Some people do react to certain preservatives or to synthetic fragrance ingredients. But the reaction rate for the common “clean” villains is low, and often lower than for the plant extracts marketed as their replacements. Removing a preservative also has a cost: without one, water-based products grow bacteria and mould.

What “green” and “eco” claims have to prove

“Green” is a different kind of word, because it’s about the planet rather than your skin. That puts it under Canada’s Competition Act, enforced by the Competition Bureau, rather than under Health Canada.

The Bureau’s guidance on environmental claims, published June 5, 2025, sets out principles. Claims must be truthful in both their literal meaning and the general impression they create. Claims about a product’s environmental benefits should be backed by adequate and proper testing done before the claim is made. And vague claims are risky: the Bureau’s own example is “eco-friendly”, which can suggest a product is good for the environment across its whole life cycle when the evidence covers only one part.

That’s a useful lens for a shampoo bottle. “Green” on its own is the vague version. “Bottle made with 50 percent recycled plastic” or “surfactants readily biodegradable” are specific claims a company can be held to.

How to read past the words

If the labels won’t tell you what’s in the bottle, the ingredient list will. In Canada, cosmetics must list ingredients using a standard naming system called INCI, and starting in 2026 the most common fragrance allergens must be named individually rather than hidden under “parfum”. That’s more useful than any front-of-pack word.

A few habits that help:

• Turn the product around and read the list. Ingredients appear roughly in order of amount, so the first five or six tell you what the product mostly is.
• If you’ve reacted to skin care before, look for the specific names of essential oils and fragrance allergens rather than trusting “natural”.
• Treat “free of” lists as a description of the brand’s marketing choices, not as evidence that what’s left is gentler.
• For environmental claims, look for a number, a standard or a certification rather than an adjective.
• If a rash keeps coming back, a doctor or dermatologist can do patch testing, which identifies the actual ingredient you react to. It’s far more reliable than guessing from labels.

You don’t have to give up products you like because they say “natural” or “clean”. Just don’t let the word make the decision. Your skin reacts to specific molecules at specific amounts, and the only place those are written down is the ingredient list.