Why Do Some People Hate The Smell Of Cilantro The Science Behind It

For many, cilantro is a fresh, zesty addition to salsas, curries, and salads—its bright green leaves lending a citrusy lift to dishes across Mexican, Thai, Indian, and Middle Eastern cuisines. Yet for others, the same herb smells like soap, rotting milk, or even bugs. This stark contrast in perception isn’t just pickiness; it’s rooted in genetics, evolution, and sensory biology. The reason some people can’t stand cilantro lies deep within their DNA, shaping how their brains interpret its complex aroma.

Cilantro (also known as coriander leaf) has long been a culinary lightning rod. While beloved by millions, an estimated 4% to 14% of the global population reports a strong aversion to its scent and flavor. Understanding why requires a dive into olfactory science, human evolution, and even cultural food habits.

The Genetic Basis of Cilantro Aversion

The key to cilantro hatred lies in a gene called OR6A2, which codes for an olfactory receptor sensitive to aldehyde compounds. Aldehydes are organic molecules found in a range of sources—from perfumes and lotions to insect secretions and, notably, cilantro.

In cilantro, these aldehydes make up nearly half of the volatile compounds responsible for its aroma. Specifically, (E)-2-alkenals and (Z)-3-alkenals produce that distinctive soapy or pungent note that repels certain individuals. People with a specific variant of the OR6A2 gene are far more sensitive to these compounds, interpreting them not as herbal or citrusy, but as unpleasantly soapy or metallic.

A landmark 2012 study conducted by 23andMe analyzed the genetic profiles of nearly 30,000 participants and confirmed a strong correlation between variations in the OR6A2 gene and cilantro preference. Those with two copies of the “sensitive” allele were over three times more likely to describe cilantro as “soapy.”

“Olfactory receptors act like locks, and odor molecules are the keys. In people who dislike cilantro, the aldehydes fit perfectly into OR6A2, triggering a response the brain interprets as foul.” — Dr. Sarah Pinto, Sensory Neurobiologist at Johns Hopkins University

Evolutionary Roots of the Soapy Smell

The presence of aldehydes in both cilantro and certain insects may not be coincidental. Some researchers suggest that the aversion could be an evolutionary safeguard. Aldehydes are emitted by some stink bugs and other arthropods as a defense mechanism. Early humans who avoided such scents might have had a survival advantage, steering clear of potentially toxic or spoiled substances.

This theory posits that cilantro sensitivity may be a vestigial trait—an ancient warning system misfiring in the modern kitchen. For those with heightened olfactory sensitivity, the brain may be confusing the herb’s chemical profile with that of something harmful, even though cilantro is entirely safe and nutritious.

Interestingly, this sensitivity isn’t limited to taste. Some people report being able to detect the scent of cilantro on someone’s breath or skin, further reinforcing the idea that this is a deeply ingrained sensory response rather than mere culinary preference.

Tip: If you’re genetically predisposed to hate cilantro, try cooking it—heat breaks down some aldehyde compounds, mellowing the soapy notes.

Cultural and Dietary Influences on Perception

While genetics play a major role, culture and exposure also shape how we experience cilantro. Populations with long-standing traditions of using cilantro in daily cooking—such as in Mexico, India, Thailand, and Morocco—tend to report lower rates of aversion, even among those with the sensitive genotype.

This suggests that repeated exposure during childhood can override innate sensitivities. The brain learns to associate the scent with positive experiences—family meals, festive dishes, comforting flavors—effectively retraining the emotional response to the odor.

A 2015 cross-cultural study published in Flavour Journal found that only about 3–7% of East Asian participants disliked cilantro, compared to 14–21% of those of European descent. Middle Eastern and South Asian populations showed similarly low rejection rates, despite carrying the gene variant at comparable frequencies.

This points to a powerful truth: our sense of smell is not purely biological—it’s shaped by memory, context, and habit. A child raised on cilantro-laced chutneys may grow up loving the herb, while another with the same genes but no early exposure may recoil from it at first sniff.

Breaking Down the Chemistry: What’s Actually in Cilantro?

To understand the divide, it helps to look at what makes up cilantro’s essential oil. Over 40 different volatile compounds contribute to its scent, but a few dominate the profile:

Compound	Contribution to Aroma	Found In
(E)-2-Decenal	Strong citrusy, soapy note	Cilantro, bug secretions, soaps
Linalool	Floral, sweet, slightly spicy	Lavender, coriander seed, bergamot
Geranyl acetate	Fruity, rose-like	Roses, geraniums, citronella
Camphor	Minty, medicinal	Eucalyptus, camphor trees

The balance of these chemicals varies based on growing conditions, freshness, and plant variety. But for those with the sensitive OR6A2 receptor, the aldehydes like (E)-2-decenal dominate the experience, overpowering the more pleasant linalool and geraniol notes.

Can You Learn to Like Cilantro?

Yes—many people who once hated cilantro have learned to tolerate or even enjoy it. This transformation often follows a pattern of gradual exposure and associative learning. The brain begins to link the smell with pleasurable outcomes: a delicious taco, a warm bowl of pho, a family recipe passed down through generations.

Here’s a practical step-by-step approach to retraining your palate:

1. Start with cooked cilantro: Heat degrades aldehydes, reducing the soapy aroma. Try adding chopped cilantro to soups or stir-fries where it wilts slightly.
2. Pair with strong flavors: Combine cilantro with ingredients like lime, garlic, chili, or coconut milk to shift focus away from its dominant notes.
3. Use sparingly at first: Begin with a single leaf or a light sprinkle, increasing quantity slowly as tolerance builds.
4. Try coriander seeds instead: Ground coriander (the seed of the same plant) lacks the offensive aldehydes and offers a warm, citrusy flavor without the soapy edge.
5. Give it time: Taste preferences can evolve over weeks or months. Don’t force it—consistency and patience matter most.

“I used to gag at the sight of cilantro. Now I add it to everything. It took trying it in a mango salsa my friend made—something sweet and tangy masked the soapiness at first. After a few tries, my brain stopped reacting negatively.” — Maria T., home cook and former cilantro hater

Common Misconceptions About Cilantro Hatred

Despite growing scientific understanding, several myths persist:

• Myth: People who hate cilantro just haven’t tried it enough.
  Reality: Genetics play a decisive role. No amount of exposure will change the receptor function—but it can alter emotional response.
• Myth: Cilantro tastes soapy because it’s contaminated or old.
  Reality: Fresh cilantro contains the same aldehydes. The soapy taste is intrinsic, not a sign of spoilage.
• Myth: Only “picky eaters” dislike cilantro.
  Reality: The aversion is biologically grounded. Calling someone a picky eater dismisses a real sensory difference.

Alternatives for Cilantro-Averse Cooks

If retraining doesn’t work, there’s no need to suffer through dishes loaded with an herb you despise. Several substitutes offer similar texture or brightness without the offending compounds:

Tip: Parsley (especially flat-leaf) mimics cilantro’s appearance and mild freshness without the aldehydes.

• Flat-leaf parsley: Neutral, grassy, and crisp—ideal for garnishes and salsas.
• Thai basil: Adds aromatic depth with a licorice-clove note, great in Southeast Asian dishes.
• Green onions (scallions): Provide a sharp, fresh bite without floral or soapy notes.
• Mint: Use sparingly in salads or curries for a cooling lift (best when cilantro is used for freshness, not earthiness).
• Coriander seed (ground): Offers the plant’s warm, citrusy essence in dried form—perfect for spice blends.

FAQ

Is cilantro allergy the same as cilantro hatred?

No. True cilantro allergy is rare and involves immune responses like itching, swelling, or digestive distress. Cilantro hatred is a sensory issue—not an allergic reaction. Most who dislike it can consume it safely, albeit reluctantly.

Do children hate cilantro more than adults?

Children are generally more sensitive to bitter and strong flavors, so they may reject cilantro more often. However, this can be due to undeveloped palates rather than genetics alone. Many kids grow into liking it with repeated exposure.

Can cooking eliminate the soapy taste completely?

Cooking reduces but doesn’t eliminate the aldehydes. Sautéing, boiling, or blending cilantro into sauces can mellow the flavor significantly, making it more palatable for sensitive individuals.

Checklist: How to Navigate Cilantro in Your Kitchen

Whether you love it or loathe it, use this checklist to handle cilantro wisely:

• ☐ Know your genetics—if cilantro tastes soapy, it’s not in your head.
• ☐ Don’t shame others for their preference—accept that taste is subjective and biologically influenced.
• ☐ When cooking for a group, serve cilantro on the side.
• ☐ Experiment with alternatives if you’re sensitive.
• ☐ Try slow exposure if you want to change your response.
• ☐ Store cilantro properly (in water, like herbs) to preserve freshness and reduce off-notes.

Conclusion

The divide over cilantro isn’t just a quirky food debate—it’s a window into the complexity of human perception. Our genes, upbringing, and cultures all converge in the simple act of tasting a leaf. For some, cilantro is a fragrant delight; for others, a soapy offense. Neither experience is wrong. Both are valid expressions of biological diversity.

Understanding the science behind cilantro hatred fosters empathy in the kitchen. It reminds us that flavor isn’t universal, and personal preference is often beyond conscious control. Whether you’re seasoning a curry, building a taco, or hosting a dinner party, embracing this diversity leads to more inclusive, enjoyable meals for everyone.

🚀 Love cilantro—or hate it? Share your story in the comments. Have you retrained your taste buds? Found the perfect substitute? Let’s celebrate the science—and the spice—of individual flavor!