Myrcene in Your Hair. Should You Be Concerned?

9 days ago

I remember the first time I came across the word myrcene. It was buried in the ingredient list of a new hair oil I had just purchased. It sounded chemical-y, almost intimidating, like something I should probably Google before putting on my scalp. And so, I did.

That quick search sent me spiraling down a rabbit hole of conflicting information. Some sources hailed myrcene as a natural, beneficial compound found in plants like mangoes, lemongrass, and basil. Others waved red flags, labeling it a carcinogen.

Wait. A carcinogen? Something that could cause cancer?

I stood there, bottle in hand, debating whether to toss it in the trash or give it a chance. If you’ve ever found yourself in a similar situation; trying to figure out whether an ingredient is friend or foe, then this article is for you.

What Is Myrcene?

Myrcene (pronounced mur-seen) is a naturally occurring compound known as a monoterpene. If you’re wondering what a monoterpene is, think of it as a scent molecule. It’s the reason why some plants and essential oils have that rich, earthy, almost spicy aroma.

If you’ve ever cut open a ripe mango and taken a deep breath, that slight herbal, musky scent you detect? That’s myrcene. If you’ve used lemongrass tea for relaxation or rubbed fresh basil between your fingers, you’ve encountered it too.

This little compound is found in nature more often than you think:

Mangoes: (which is why some people swear that eating mango before consuming cannabis enhances its effects)
Hops: (yes, the same ingredient used in beer)
Bay leaves
Basil
Thyme
Cannabis

But what is it doing in your hair products?

Why Is Myrcene Used in Hair Care?

In hair products, myrcene is often added for three main reasons:

1. Fragrance Enhancement

Myrcene has a slightly sweet, herbal scent that helps enhance the aroma of shampoos, conditioners, and leave-in treatments. It’s commonly used in natural hair products that rely on plant-based (essential oils) fragrances instead of synthetic perfumes.

2. Anti-Inflammatory & Soothing Properties

Myrcene has been studied for its ability to reduce inflammation. If you deal with scalp irritation, dandruff, or itchiness, products containing myrcene (often through essential oils like bay leaf or basil oil) may help calm your scalp and prevent excessive flaking.

3. Potential Hair Growth Benefits

Some studies suggest that myrcene could help increase circulation in the scalp, which is a key factor in promoting hair growth. When blood flow to the scalp is improved, hair follicles receive more nutrients, leading to stronger, healthier hair over time.

Wait… But Isn’t Myrcene a Carcinogen?

This is where things get tricky.

Yes, myrcene has been labeled as a possible carcinogen. But before you panic, let’s clarify what that actually means.

In 2010, California’s Office of Environmental Health Hazard Assessment (OEHHA) added myrcene to its Proposition 65 list of chemicals that could potentially cause cancer. But here’s the catch: this classification was based on studies where animals (mostly mice and rats) were exposed to extremely high doses of myrcene over long periods.

And when I say high doses, I mean doses far beyond what you’d ever get from using a hair product.

For context, consider this:

Many everyday foods contain naturally occurring carcinogens when tested in massive amounts. For example, acrylamide (found in fried foods like French fries and toast) has also been classified as a carcinogen in lab tests, but people still enjoy their fries without fear.
Coffee contains trace amounts of a compound that has been flagged as a potential carcinogen too. Yet, studies have also shown that coffee can reduce the risk of certain diseases, including Parkinson’s and Alzheimer’s.
Even the air we breathe in big cities contains compounds that, in high enough concentrations, could be labeled as harmful.

The key thing to remember is dosage matters. There’s a big difference between being exposed to something in tiny, naturally occurring amounts versus having large amounts pumped into your body every single day.

So, Should You Be Worried About Myrcene in Your Hair Products?

Not really. The amounts found in natural hair products are too low to pose a significant risk. Plus, myrcene isn't some lab-made, artificial compound—it’s something nature produces on its own, and we’ve been consuming it in small amounts through food for centuries.

In fact, when used in the right way, myrcene has some great benefits for your hair:

✔ Helps retain moisture – If your hair struggles with dryness, myrcene-rich ingredients (like bay leaf oil) can help lock in hydration.

✔ Encourages stronger strands – Some research suggests that myrcene’s anti-inflammatory properties may help reduce scalp stress, which can minimize hair loss.

✔ Supports a healthy scalp – A clean, balanced scalp = optimal hair growth. Since myrcene is found in natural plant oils, it can work alongside other ingredients to maintain scalp health.

Final Thoughts: Fear or Friend?

It’s easy to get scared when you see a word like carcinogen attached to an ingredient. But context is everything. Myrcene is a naturally occurring compound found in things we eat and use daily. When present in small, natural amounts (like in hair products), it’s unlikely to be harmful—and may even be beneficial.

Rather than rushing to throw away products that contain myrcene, take a more balanced approach:

Read labels carefully – Look for natural sources of myrcene, like essential oils (lemongrass, bay leaf, basil).
Focus on overall hair health – A single ingredient doesn’t make or break a product. Look at the whole formula and how it benefits your hair.
Keep things in perspective – If you’re already eating mangoes and basil, using myrcene in your hair is far from dangerous.