Why Some People Find Foods Bitter: The TAS2R38 Gene

Last reviewed: May 12, 2026 Last updated: May 12, 2026

Written by: Jay Hastings , CEO of PlexusDx

Jay Hastings is the CEO of PlexusDx, a precision health company focused on genetic testing, blood biomarker insights, and personalized wellness recommendations. He has more than 20 years of experience across healthcare innovation, genomics, laboratory operations, healthcare investing, and strategic finance. His work has included scaling healthcare startups, leading CLIA lab integrations, and helping expand consumer access to precision health tools.

Medically reviewed by: Jayden Lee, PharmD, EMBA

Jayden Lee, PharmD, EMBA, is the PlexusDx Medical Science Liaison with a PharmD and MBA specializing in pharmacogenomics and clinical product development, with a proven ability to bridge the gap between genomic research and practical patient outcomes. Dr. Lee has more than 10 years of professional experience in clinical pharmacy, academia, and research.

This article is part of the PlexusDx Education Hub — your resource for evidence-based, DNA-driven health insight. Browse all Diet & Genetics education.

Hand a plate of raw broccoli, black coffee, or tonic water to a room full of people and you will get wildly different reactions. Some barely notice any bitterness; others recoil as if the food were spoiled. This is not pickiness or imagination — it is largely written into your DNA. Bitter taste perception is one of the most clearly genetic of all our senses, and the gene at the center of it, TAS2R38, helps explain why the same vegetable can be pleasant to one person and punishing to another.

Taste perception starts with your genes

Your tongue carries taste receptor cells studded with proteins that detect sweet, salty, sour, umami, and bitter compounds. Bitterness is special: humans have roughly 25 different bitter-taste receptor genes (the TAS2R family), likely because detecting bitterness historically helped our ancestors avoid toxic plants. Because these receptors are proteins built from genetic instructions, inherited differences in the genes translate directly into differences in what you taste. Two people can eat the identical food and genuinely experience different intensities of bitterness.

TAS2R38: the PROP and PTC bitter receptor

The best-characterized bitter gene is TAS2R38, which encodes a receptor that detects compounds called PROP and PTC — chemicals related to those found in cruciferous vegetables like broccoli, kale, and Brussels sprouts. Three variants (rs713598, rs1726866, and rs10246939) combine into two common versions of the receptor: a “taster” form (often written PAV) and a “non-taster” form (AVI). The taster version binds these bitter compounds efficiently, producing a strong response; the non-taster version responds weakly.

Tasters, non-tasters, and supertasters

Because you inherit one TAS2R38 copy from each parent, people generally fall into three groups. Non-tasters (two AVI copies) find many bitter foods mild. Tasters (at least one PAV copy) perceive clear bitterness. A subset with high receptor sensitivity, sometimes called supertasters, experience bitter, spicy, and even fatty foods more intensely overall. These categories are a spectrum, not rigid boxes, and other genes and factors fine-tune the final experience.

Why bitterness perception shapes diet and health

Taste genetics ripples into food choices. People who perceive strong bitterness may eat fewer cruciferous and leafy green vegetables, potentially nudging their diet away from foods rich in fiber and micronutrients. Some research has explored links between taster status and preferences for sweeter foods, alcohol acceptance, and even vegetable intake in children. Understanding your genetic tendency does not excuse avoiding vegetables — it helps you find preparation methods (roasting, pairing with fat or acid) that tame bitterness so healthy foods become enjoyable.

Beyond TAS2R38: the wider taste network

TAS2R38 is the headline gene, but it is not alone. Other bitter receptors such as TAS2R16 and TAS2R19 influence responses to different compounds, and genes involved in sweet and fat perception shape the overall flavor experience. This is why two people who share the same TAS2R38 genotype can still differ in their tastes. Taste is a network trait, and mapping several genes gives a richer picture than any single variant.

What genetic insight adds to your plate

Knowing your taste genetics reframes food preferences as biology rather than stubbornness. The Precision Peptide Genetic Test analyzes 14 pathways, 49 peptides, 150+ genetic insights, including taste- and diet-related pathways where genes like TAS2R38 operate. That pathway-level context can help you and a registered dietitian or provider build eating habits that work with your palate instead of against it — genetics as a guide, not a guarantee.

Frequently Asked Questions

What gene makes some people taste bitterness more strongly?

TAS2R38 is the primary gene. Its variants (rs713598, rs1726866, rs10246939) form “taster” and “non-taster” versions of a bitter receptor that detects PROP and PTC compounds found in cruciferous vegetables. Taster versions bind these compounds efficiently, producing stronger perceived bitterness from the same food.

Are supertasters healthier or unhealthier?

Neither, inherently. Supertasters perceive bitter, sweet, and fatty foods more intensely, which can reduce vegetable intake but may also lower tolerance for very sweet or fatty foods. Diet quality depends on food choices and preparation, not taster status alone, so the trait cuts both ways.

Can I train myself to like bitter foods?

Yes, to a degree. Genotype sets your baseline sensitivity, but repeated exposure and smart preparation — roasting vegetables, pairing them with fat, salt, or acid — can reduce perceived bitterness over time. Many strong tasters learn to enjoy foods they once avoided through gradual, consistent exposure.

Does a genetic test tell me exactly what to eat?

No. A genetic test reveals pathway-level tendencies, such as your likely bitter-taste sensitivity, not a prescriptive meal plan. It offers educational context you can pair with guidance from a registered dietitian or provider to shape food choices that suit your palate and goals.

Want to know whether you’re a taster, non-taster, or supertaster? Take the Precision Peptide Genetic Test to explore 14 pathways, 49 peptides, 150+ genetic insights at the DNA level. PlexusDx tells you about your biology — your provider helps you decide what to do with it.

Disclaimer: The Precision Peptide Genetic Test analyzes how your genes influence peptide-related biological pathways. It does not recommend, prescribe, or determine which peptides you should use, and it does not diagnose, treat, cure, prevent, or manage any disease or condition. Genetics is a guide, not a guarantee. Consult a qualified healthcare provider before beginning any peptide protocol or making changes to your health plan.

Medical and Editorial Standards

Medical review process: This article was reviewed for medical accuracy, scientific clarity, evidence alignment, and appropriate discussion of genetics, medications, supplements, biomarkers, and health-related claims.

Sources and evidence: PlexusDx educational content is developed using peer-reviewed research, clinical literature, reputable medical references, and, where applicable, public health or regulatory guidance. References are included at the end of the article when scientific, medical, or health-related claims are discussed.

Commercial transparency: PlexusDx offers genetic testing, blood biomarker testing, personalized supplement recommendations, and related precision wellness services. Product mentions are intended to help readers understand available options and should not be interpreted as medical advice.

Important disclaimer: PlexusDx educational content is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about medications, supplements, genetic testing, lab testing, or health-related care.

This article is part of the PlexusDx Education Hub. Browse all Diet & Genetics education.