Debunked: Everything That's Wrong With the Yuka App

What is the Yuka app?

Founded by two brothers in 2016 and reporting a staggering 85 million users worldwide, Yuka is a mobile app that allows you to scan barcodes of cosmetic and food products to determine ‘their impact on health and the environment’. In one scan, Yuka provides products with a score out of 100 based on the ingredients in the formula.

How does Yuka work?

For the purpose of this article, we will focus on the use of Yuka for cosmetic products. Yuka classifies each ingredient in a formula into one of four categories:

• Risk-free (green dot)
• Low risk (yellow dot)
• Moderate risk (orange dot)
• Hazardous (red dot)

The app then gives an overall score out of 100 to the product, to determine its overall colour rating. This overall score is determined by the level of the highest-risk ingredient present in the formula. This means:

• If a ‘hazardous’ ingredient is present, even in a very tiny percentage, the overall score for the product will automatically be red (lower than 25/100)
• If the highest-risk ingredient is labelled as ‘moderate-risk’, the product’s overall score will automatically be orange (lower than 50/100)

The specific score is then based on all other ingredients in the formula, with certain types of ingredients (e.g., so-called potential carcinogens or allergens) posing penalties to the overall score.

Why the Yuka app is fundamentally flawed

The methodology by which Yuka rates products is completely flawed. The system focuses on single ingredients and their so-called ‘risks’, which is fundamentally incorrect. Here’s why:

1. Yuka does not factor in dosage.

The toxicity of an ingredient is dose-dependent. Think of it like this: Paracetamol can be toxic if taken in excess—does that mean you should never take it? Of course not. Even if an ingredient has the potential to pose a risk, this will be at a far, far higher dosage than would ever be used in a cosmetic product. Every single ingredient added to a cosmetic product has been thoroughly tested for safety and will only ever be added at a dosage far below any potential toxic level.

2. Focusing on single ingredients in isolation does not reflect a product’s formula.

It is a fallacious overestimation to rate the overall formula of a product based on single ingredients in isolation. One ingredient does not determine the whole formula, especially if it is present in low amounts.

3. There is a lack of evidence for Yuka’s claims.

The app focuses too heavily on hearsay over credible evidence — using uncertified studies to back up its ingredient ratings. For example, phenoxyethanol—a common preservative—is listed as a ‘moderate risk’ ingredient. Yuka’s justification for this is below:

“Its maximum content in products is 1% in the EU, UK and Australia. On the other hand, it is not regulated in the USA or Canada. Some studies question the 1% threshold considered safe by the CSSC. There is therefore a risk if used in products that are not rinsed off babies' bottoms (creams, wipes, etc.). Furthermore, if several cosmetics containing phenoxyethanol are used on a daily basis (particularly sun creams), the level of health concern could be exceeded.”

Firstly, using the fact that some studies question the 1% threshold as reasoning to rate an ingredient as ‘moderate risk’ is unreasonable, especially considering that this means the overall product cannot be rated over 50/100. Secondly, the ingredient may not even be present at a 1% concentration in said product.

A final word on fearmongering

We could go on, but you get the gist—the Yuka app is built on a completely oversimplified methodology and is not a reliable source of information. Formula and dose are everything, and ignoring the vast nuances of cosmetic and skincare formulation to rate an entire product on an isolated ingredients without any context or dose consideration is mythical. All this does is spread fear and confuse the consumer even further. It is a dangerous and wildly misleading source, and in a world where skincare and cosmetic products can be confusing enough, the last thing we need is the Yuka app.