Why does cilantro bother some people? The genetic science behind the taste

November 28, 2025 •

4 min read

It's estimated that between 3% and 21% of the population experiences cilantro as a noxious, soapy herb. This polarizing reaction is not simply a matter of personal preference but is rooted in a person's genetic makeup, particularly their olfactory receptors.

Quick Summary

This article explores the genetic and chemical factors that cause a taste aversion to cilantro, detailing the role of the OR6A2 gene and the aldehydes that give the herb its distinctive, and to some, soapy flavor. It also examines cultural influences on this perception.

Key Points

Genetic Link: The main reason for cilantro aversion is a genetic variation in the OR6A2 gene, which makes some individuals highly sensitive to the herb's soapy-flavored aldehydes.
Aldehydes Cause the 'Soapy' Taste: Cilantro contains chemical compounds called aldehydes, which are also found in soap. People with the specific genetic variant perceive these compounds more strongly, leading to an unpleasant taste.
Cultural Differences in Prevalence: The prevalence of the cilantro-aversion gene varies by ethnicity, with some populations showing a much lower incidence, possibly due to long-term dietary exposure.
Exposure Can Influence Perception: While genetically predisposed, some people can train their brains to tolerate or even enjoy cilantro through repeated, positive exposure, especially if the herb is crushed.
Cilantro Leaves vs. Coriander Seeds: The soapy flavor is isolated to the fresh cilantro leaves. The seeds, known as coriander, have a completely different flavor profile and are generally not a problem for those with the aversion.
Evolutionary Hypotheses: One theory suggests the aversion is an evolutionary holdover, acting as a defense mechanism against potentially toxic plants that contain similar aldehydes.
Olfactory Receptors Play a Major Role: The perception of cilantro's soapy taste is largely driven by the sense of smell rather than just taste buds, as it's the olfactory receptor genes that are primarily affected.

The Chemical Culprit: Aldehydes

Aldehydes are chemical compounds in cilantro leaves that give the herb its unique aroma. While many perceive this as fresh and citrusy, others with a specific genetic variation experience a soapy or bitter taste. Different types of aldehydes contribute varying aromas, from 'fruity' and 'green' to 'soapy' and 'pungent'. Crushing or chopping the leaves intensifies the release of these volatile compounds.

The Genetic Link: The OR6A2 Gene

Research, including a large-scale genome-wide association study, points to a genetic variant, rs72921001, located near olfactory receptor genes on chromosome 11, as being linked to the soapy perception of cilantro. The OR6A2 gene in this cluster plays a key role. A variation in this gene causes heightened sensitivity to certain aldehydes, making them perceive a soapy taste more strongly. This highlights the significant role of smell, closely linked to taste, in this reaction. Therefore, disliking cilantro is a biological, not just psychological, phenomenon for many.

Beyond Genetics: The Role of Culture and Exposure

Beyond genetics, cultural background and repeated exposure can shape one's perception of cilantro. The gene variant associated with aversion varies globally, being less common in populations with a history of using cilantro in their cuisine. This suggests that environmental factors and diet may modify genetic predispositions over time.

Some individuals have reported overcoming their aversion through repeated exposure, especially when cilantro is used in ways that minimize the impact of aldehydes, such as when cooked or crushed. Building positive associations with the food can also help. However, this is not always effective, and many individuals with the genetic predisposition continue to dislike the herb.

The Cilantro Divide: A Comparison


Aspect	Cilantro Lovers	Cilantro Haters
Key Chemical Perception	Perceive a balance of fruity, fresh, and citrusy aldehydes.	Highly sensitive to the pungent, soapy aldehydes.
Genetic Basis	Likely possess a different variation of the OR6A2 gene or other influencing genes.	Possess the specific OR6A2 gene variant that detects soapy aldehydes.
Flavor Experience	Enjoy a bright, herbal taste that complements many dishes.	Experience a foul, soapy, or metallic taste that ruins a dish.
Overcoming Aversion	No aversion to overcome.	Can potentially lessen aversion through repeated exposure, though often unsuccessful.

An Evolutionary Hypothesis

One theory suggests that a strong aversion to cilantro's aldehydes may have provided an evolutionary advantage, helping early humans avoid potentially toxic plants with similar compounds. While speculative, this could explain why the trait persists.

Conclusion

The perception of cilantro is a complex mix of genetic, chemical, and environmental factors. The OR6A2 gene's sensitivity to aldehydes is a primary driver of the soapy taste for some. While cultural exposure and attempting to overcome the aversion can play a role, the fundamental dislike is a biological reality. Understanding this genetic basis helps explain the varied reactions to cilantro. For those who dislike it, using alternatives like parsley or lime juice is a viable option.

A Note on Further Reading: For in-depth scientific research on the genetic links to cilantro aversion, the journal Flavour is a key source.

Frequently Asked Questions About Cilantro Aversion

Q: Is disliking cilantro really due to genetics? A: Yes, scientific research has identified a specific genetic component linked to the aversion. The OR6A2 gene is associated with a heightened sensitivity to certain aldehydes in cilantro, which can make it taste like soap.

Q: What are aldehydes, and why are they important? A: Aldehydes are organic chemical compounds that contribute to the aroma and flavor of cilantro. For individuals with a particular gene variant, these same compounds taste and smell like soap, which is a byproduct of their structure.

Q: Can a person overcome their cilantro aversion? A: Some people have found that repeated exposure to cilantro, especially in cooked or crushed forms, can lessen their aversion over time, but it is not a guaranteed solution. Environmental factors can influence genetic predisposition.

Q: Why does the prevalence of cilantro aversion differ by ethnicity? A: Studies show that the gene variant causing the aversion is less common in populations where cilantro is a staple ingredient, such as those of South Asian or Latin American descent. This suggests that cultural dietary habits and ancestry play a significant role.

Q: Are there any alternatives for cilantro haters? A: Yes, suitable substitutes include flat-leaf parsley, which is in the same family but lacks the soapy aldehydes, and lime juice, which offers a similar citrusy brightness. Other options include Thai basil or dill.

Q: Is it true that coriander seeds are different from cilantro? A: Yes. Coriander seeds are the dried, ripened fruit of the same plant and have a warm, spicy, and citrusy flavor profile, not the soapy taste associated with the leaves. People who dislike fresh cilantro can often enjoy coriander seeds.

Q: Does cooking cilantro reduce the soapy taste? A: Yes, cooking or crushing cilantro can help to break down the aldehydes, which may reduce the intensity of the soapy flavor for some individuals. However, this method does not work for everyone.

Frequently Asked Questions

If cilantro tastes like soap to you, it is likely due to a genetic variation in your olfactory receptors, specifically the OR6A2 gene, which makes you more sensitive to the aldehydes in the herb.

No, it is primarily a biological issue. While personal experiences can influence food preferences, the core aversion to cilantro is rooted in a person's genetics and the way their body processes certain chemical compounds.

Some people have been able to reduce their dislike with repeated exposure, especially to crushed or cooked forms of the herb. However, this is not always successful, and for many, the aversion remains.

The varying prevalence of the gene variant across different populations influences its culinary use. Regions where the aversion is less common, like in some parts of Central America and India, have integrated cilantro more deeply into their traditional dishes.

Cilantro is in the parsley family, but its unique aldehydes are what cause the soapy taste. Other herbs in the family, like parsley, dill, or cumin, do not typically cause the same reaction.

Not necessarily. While the OR6A2 gene variant significantly increases the likelihood of an aversion, other genes and environmental factors can also influence a person's perception of taste.

Yes, since the tendency is based on genetics, it can be passed down. However, the genetic component is complex, and cultural exposure can also influence whether a child ultimately develops a dislike for the herb.