Maui is a shampoo brand that’s a blend between luxury and convenience. The shampoo is branded like a luxury shampoo, but is priced at affordable, drugstore rates.

But does Maui Shampoo contain research-backed ingredients for improving hair thickness and hair quality? Does it contain any unhealthy ingredients? 

In this article we’ll answer all of these questions and more, as we analyze the ingredients in one of Maui’s most popular shampoos (Thicken & Restore) to give our take on whether or not it’s likely to improve hair quality, and whether or not it's healthy.

We’ll also compare Maui to other popular shampoo brands like Monday Shampoo to pick our winners (and losers).

Key takeaways:

• Contains active ingredients shown to improve hair quality
• Contains some inactive ingredients we consider unhealthy
• We do not currently recommend Maui Shampoo

Ingredient Analysis

The ingredients in Maui Thicken & Restore Shampoo are shown below:

Bambusa arundinacea (bamboo) stem extract is often included in shampoo formulations, but we’re not sure why. We can’t find any clinical evidence that it improves hair quality, nor does the brand cite any on their product page at the time of publishing this article.

Coconut water is another strange ingredient choice in our opinion, given that coconut oil has such strong research backing for hair health.

A medical review published in the Journal of Cosmetic Science found that coconut oil significantly protected hair strands from damage.

Melia azadirachta was described as a “hair growth inducer” in a 2013 medical review.

Tapioca starch is a natural hair softening agent and thickener according to a medical review published in the Polymers journal.

Castor oil is clinically shown to improve hair shine, as we documented in our review of another shampoo brand called Kitsch.

Aloe vera can restore hydration to the skin according to a 2022 medical review, which suggests it may optimize scalp health.

Clearly there are a number of research-backed active ingredients in this formulation.

However, there are also two inactive ingredients that we consider to be questionable from a health perspective.

Diazolidinyl urea is a synthetic preservative that releases formaldehyde, which is a carcinogen (meaning it can cause cancer), according to a medical review published in the Contact Dermatitis journal. 

Iodopropynyl butylcarbamate is another synthetic preservative that was described as “a potential new contact allergen” in a 2002 medical review.

Fragrance is a broad categorical term that applies to a wide range of different chemical compounds, and as we documented in our Kristin Ess Shampoo review article, at least one medical review describes fragranced consumer products as a serious risk to human health.

Overall, we consider Maui Thicken & Restore Shampoo likely to improve hair quality and appearance, however we don’t currently recommend this product due to the three inactive ingredients highlighted above.

Maui Shampoo vs. Popular Shampoo Brands

Here's how Maui Shampoo compares to other popular shampoo brands in terms of potential effectiveness and healthiness, in our opinion:

Monday Shampoo

Contains hydrolyzed wheat protein, which is clinically shown to naturally condition and soften hair.

Contains fragrance, but is free from any formaldehyde-releasing preservatives, which gives Monday the edge from a health perspective.

Winner: Monday Shampoo

Redken Shampoo

Contains a fragrance ingredient which is clinically shown to be harmful to lung tissue, as we discussed in our Redken shampoo review article.

Also contains five other inactive ingredients we consider unhealthy.

Winner: Maui Shampoo

Olaplex

Contains fragrance, but no other inactive ingredients we consider as unhealthy as diazolidinyl urea.

Winner: Olaplex

Our Clean Hair Care Picks

Acure Vivacious Volume Shampoo is our top shampoo pick.

It contains argan oil which is clinically shown to help protect hair from damage.

Ritual HyaCera is our top hair growth supplement.

This supplement contains wheat oil extract, and a 2024 clinical trial reported that a wheat lipid complex had "a reducing effect on hair shedding and a stimulating effect on hair reappearance and growth."

Both of the products recommended in this section are free of ingredients we consider to be unhealthy.

Maui Shampoo Pros and Cons

Pros:

• Many research-backed active ingredients
• Should improve hair shine
• Should improve hair quality
• May improve scalp health
• Available in-store and online
• Affordable
• Dermatologist-recommended

Cons:

• Contains two synthetic preservatives
• Contains fragrance

Conclusion

Maui Shampoo is one of the better shampoos for the price from an efficacy perspective, but one of the worst shampoos from a health perspective, in our opinion.

This brand uses active ingredients that have been shown in research studies to improve hair shine, support hair growth, and hydrate the skin.

However, Maui also uses two synthetic preservatives, one of which has been clinically shown to release a carcinogen. 

The Maui shampoo product analyzed in this article also contains fragrance.

We consider Maui Shampoo to be a healthier option than Redken Shampoo, but a less healthy option than Monday Shampoo and Olaplex.