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Function of Beauty Review: Does Individualized Shampoo Work?

Function of Beauty Review: Does Individualized Shampoo Work?

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Read our Editorial Guidelines to learn more about what makes our site the premier resource for online health information.

Read our Editorial Guidelines to learn more about what makes our site the premier resource for online health information.

Function of Beauty sells extremely expensive customizable personal care products, including shampoo, body wash and more. The brand claims that they’re the “world leader” in customizable beauty and that they use only “clean, science-backed ingredients.”

In this article we’ll review the ingredients in some of Function of Beauty’s products based on medical research to see if their claims hold up.

Questionable Product Safety Announcement

The top article on Function of Beauty’s blog at the time of writing this article is an announcement that the company “Passed Major Safety Standards”.

The article goes on to detail how a company called Biorus tested Function of Beauty’s products and deemed them safe.

The article does not publish any of the results from the testing, nor does Biorus appear to, so this doesn’t provide any valuable information to consumers.

Additionally, Function of Beauty states that toxicological testing was done (which determines whether toxins exist in the formulations), but allergens are another big issue in cosmetics according to the Food and Drug Administration (FDA) and there is no mention of allergen testing.

We find this article to be unscientific, and frankly, find that it evidences a lack of respect for the intelligence of their consumers. The company doesn’t even state what toxins were tested or summarize the results or state what standards were used for the testing. They just say “hey we paid a private, for-profit research firm to test our products and the firm said our products were safe.” This is not clinical research in any legitimate sense of the term.

We hope to see better science and transparency from personal care products companies.

Ingredient Review

Consumers who order Function of Beauty products through their website will go through an individualized formulation process, but the brand also sells products at Target, which allows us to analyze the ingredients list for the public version of their products.

One of the first things we noticed, and were surprised by, is that Function of Beauty uses artificial coloring agents in their shampoo sold at Target. Their Straight Hair Shampoo Base with Coconut Water for sale on Target’s website contains Blue 1 and Red 33.

A medical review of the toxicology of food dyes published in the International Journal of Environmental and Occupational Health concluded that “the inadequacy of much of the testing and the evidence for carcinogenicity, genotoxicity, and hypersensitivity…indicates that all of the currently used dyes should be removed from the food supply.”

While there are greater health risks ingesting these compounds, some topically-applied compounds can still reach the bloodstream through transdermal absorption, and can irritate the skin. We recommend avoiding any cosmetic products with artificial food dyes included, and we’ve never seen these ingredients used before in a hair product that we’ve reviewed. 

The shampoo also contains fragrance, a broad categorization for a host of different chemical compounds, many of which may be harmful to human health. A medical review published in 2017 analyzed the established neurotoxicity of several categories of fragrance compounds.

We always recommend avoiding fragrance in all personal care products; even if some of the chemicals used are safe, we can’t tell which are used when the manufacturer only lists “fragrance”. If Function of Beauty were to publish which chemicals they used for their fragrances, or publish the raw data of their toxicology reports from Biorus, we would consider updating this section.

Function of Beauty’s shampoo also contains the preservative sodium benzoate, and while this is one of the most well-studied preservatives and is common in personal care products, our recommendation is to avoid preservatives since many products are free of them, and their long-term safety is questionable.

As an example of why we recommend avoiding preservatives in food and cosmetic products, this clinical trial found that phenoxyethanol, another preservative ingredient used by Function of Beauty in their custom formulations, induced cellular atrophy and death at concentrations equivalent to that approved for use in humans.

The above study was in vitro, meaning it was a test tube study, which makes the data weaker than human trials. We’re not suggesting that these preservatives in shampoo cause cellular death; we’re stating that it seems rational to use an abundance of caution and avoid ingredients which have no health benefit and seem to possess a low potential health risk.

It’s worth noting that on Function of Beauty’s site, users can select a “fragrance free” and “dye free” option when selecting their personalized cosmetic products. For consumers set on purchasing from Function of Beauty, we recommend selecting both of those options for the healthiest final product.

Like their hair care products, the only questionable ingredient in Function of Beauty’s moisturizer is the preservative phenoxyethanol. We completed a test quiz to see a full ingredients list, and there was a fragrance-free option. If that is selected, this is a relatively safe and effective formulation, but we still wouldn’t recommend it due to the preservative inclusion.

Overall it’s clear that health-conscious consumers who want to purchase Function of Beauty products should go through their site rather than purchase the commercially available versions at retail stores like Target.

Function of Beauty Vs. Prose

Many consumers are curious about whether Function of Beauty or Prose is safer and more effective, since these are the leading personalized cosmetic brands.

Our Prose shampoo reviews article reviewed the brand favorably, and we would recommend Prose over Function of Beauty. We have no affiliation with either brand so our recommendation is unbiased.

Like Function of Beauty, Prose has fragrance-free and dye-free versions of their custom formulations, which we would recommend over products with fragrance and/or dye.

The main difference is that we found the active ingredients in Prose to be more effective, and that Prose didn’t use any preservative ingredients that we found questionable.

Unhappy Customer Reviews

Function of Beauty has a somewhat notable amount of negative feedback online from users of their products. A VICE article from 2021 reported how many users were documenting that Function of Beauty products were causing hair loss.

Their Better Business Bureau (BBB) page is also overwhelmingly negative, with a review average of 1.05 out of 5 stars, and a significant number of complaints.

Any popular brand will have its detractors, so this doesn’t necessarily mean anything about the safety of the products, but hair loss is a relatively serious accusation, and it’s somewhat concerning when reported from many users at once.

It’s worth noting that there are no active lawsuits against Function of Beauty, nor any FDA actions, so we find it likely that this is just a loud minority of unhappy customers and doesn’t necessarily prove anything. We just wanted to highlight that this brand seems to have more negative reviews online than its competitors.

Better Alternative

As we mentioned in the comparison section, we would recommend fragrance-free Prose products over fragrance-free Function of Beauty products.

We also frequently recommend Dr. Bronner’s brand cosmetic products as safe, non-toxic alternatives to popular brands like Function of Beauty.

Dr. Bronner product formulations are refreshingly simple, and the brand uses essential oils for fragrance.

Their citrus hair shampoo, for example, contains organic lemon oil and organic orange oil for a natural fragrance. The product contains no ingredients that we deem unsafe, and we would recommend this product over any Function of Beauty shampoos. We have no affiliation with Dr. Bronner’s and receive no compensation for recommending them.

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Function of Beauty is a brand that seems to prioritize branding and marketing over scientific formulations.

We find it surprising that a brand highlighting their clean ingredients sells products at retailers with artificial food dye; a practice we haven’t even seen with cheaper personal care products brands.

Many consumers online have negative reviews of Function of Beauty, and we don’t recommend any of their products due to the inclusion of preservatives.

For consumers who do want to try Function of Beauty products, we would recommend their fragrance-free and dye-free options, and we would recommend purchasing from their site rather than from a retail store, because their site allows for the selection of such options.

We find that Prose and Dr. Bronner’s are healthier formulations for shampoo and soap that we would recommend over Function of Beauty.

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