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.

NQO1 and Antioxidant Defense: What Your Genotype Means for Cellular Health

Antioxidants protect your cells from damage caused by free radicals. Free radicals are unstable molecules produced by normal metabolism and increased by factors such as pollution, smoking, poor diet, and stress. The NQO1 gene makes an enzyme that helps detoxify harmful compounds and recycle antioxidants like vitamin E and coenzyme Q10. Variations in NQO1 can change how well this enzyme works, which may affect how your body handles oxidative stress.

Why NQO1 Matters

NQO1 supports several important processes:

  • Detoxifying reactive quinones and other harmful compounds so they are less damaging to cells.
  • Recycling and preserving fat soluble antioxidants such as vitamin E and coenzyme Q10 so they remain effective longer.
  • Working with other antioxidant systems to limit damage to tissues such as the brain, heart, liver, and immune system.

When NQO1 activity is reduced, the body may be less efficient at clearing damaging molecules and conserving antioxidants. That can increase sensitivity to environmental stressors like pollution and cigarette smoke, and may place more importance on lifestyle strategies that support antioxidant defenses.

Two effect alleles - GG (rs1800566)

If your genotype is GG, you carry two copies of the effect allele. This genotype is associated with significantly reduced NQO1 enzyme activity. Lower enzyme function may make it harder for your body to detoxify reactive compounds and recycle antioxidants such as coenzyme Q10 and vitamin E. As a result, you may be more vulnerable to oxidative stress from environmental exposures and lifestyle factors.

What to prioritize

  • Daily variety of colorful fruits and vegetables to supply a broad mix of antioxidants and polyphenols.
  • Include healthy fats like olive oil, avocado, nuts, and fatty fish to help absorb fat soluble antioxidants.
  • Polyphenol rich foods such as berries, green tea, cruciferous vegetables, turmeric, and dark chocolate.
  • Strictly avoid smoking and limit exposure to pollution and secondhand smoke when possible.
  • Manage stress with practices such as mindfulness, yoga, or breathing exercises.
  • Regular moderate exercise to support circulation and antioxidant enzyme systems, while avoiding excessive, prolonged intense training without adequate recovery.
  • Prioritize quality sleep for cellular repair and immune function.

Supplements to discuss with your healthcare provider

  • Vitamin C and vitamin E to support antioxidant capacity.
  • Coenzyme Q10 to support cellular energy and be recycled by antioxidant pathways.
  • N-acetylcysteine or other supplements that support glutathione, a key intracellular antioxidant.
  • Consider routine monitoring of relevant blood tests as recommended by your provider.
One effect allele - AG (rs1800566)

If your genotype is AG, you carry one copy of the effect allele. This is associated with moderately reduced NQO1 activity. Your enzyme likely works less efficiently than in people with two typical copies, so your oxidative stress response may be partially affected. Lifestyle and dietary practices that support antioxidant defenses can help compensate for this modest reduction.

What to prioritize

  • Eat a colorful, plant rich diet with plenty of vegetables and fruit each day.
  • Include healthy fats to aid absorption of fat soluble antioxidants.
  • Favor polyphenol sources such as berries, green tea, herbs and spices, and cruciferous vegetables.
  • Avoid smoking and limit environmental toxin exposures when possible.
  • Maintain regular exercise, good sleep habits, and stress management routines.

Supplements to discuss with your healthcare provider

  • Vitamin C and vitamin E if dietary intake is low.
  • Coenzyme Q10 for mitochondrial support and antioxidant recycling.
  • N-acetylcysteine or other glutathione supporting compounds when appropriate.
No effect alleles - AA (rs1800566)

If your genotype is AA, you carry two copies of the non effect allele. This indicates typical NQO1 enzyme activity, which supports effective antioxidant defense and detoxification. Your cells are likely better able to convert reactive quinones into less harmful forms and to recycle antioxidants like coenzyme Q10 and vitamin E.

What to prioritize

  • Maintain a colorful, nutrient dense diet to preserve your natural antioxidant advantage.
  • Include healthy fats to help absorb fat soluble antioxidants.
  • Continue regular physical activity, prioritize restorative sleep, and manage stress.
  • Avoid smoking to protect your antioxidant systems from unnecessary burden.

Supplement considerations

  • Most people with typical NQO1 activity can meet needs through diet, but targeted supplements such as vitamins C and E, coenzyme Q10, or glutathione precursors can be considered with your healthcare provider if you have specific concerns or low dietary intake.

Practical Diet and Lifestyle Tips

  • Aim for a variety of colors at each meal to maximize antioxidant and polyphenol intake.
  • Include cruciferous vegetables such as broccoli and Brussels sprouts to support detox pathways.
  • Prioritize whole foods over processed options to reduce exposure to pro oxidant additives.
  • Choose sources of omega 3 fats such as fatty fish, walnuts, or flaxseed to support inflammation balance.
  • Stay hydrated and limit excessive alcohol intake, which can increase oxidative load.
  • Practice stress reducing activities and aim for 7 to 9 hours of sleep per night for optimal cellular repair.

Blood Tests and Monitoring

Your healthcare provider may recommend blood tests if there are concerns about nutrient status or oxidative stress. Possible tests include vitamin C and vitamin E levels, coenzyme Q10, markers of inflammation, and standard metabolic panels. Testing can help tailor any supplement or lifestyle plan to your individual needs.

Important Disclaimer

PlexusDx provides education about genetic predispositions only. This information does not constitute medical advice. Always consult your healthcare provider before making changes to your diet, starting supplements, or changing medications or treatments. Your provider can interpret these results in the context of your health history, symptoms, and other lab findings.


If this genetic variant is present in your PlexusDx results, the following tests and reports are commonly used to explore it further:

🧬 Genetic Tests:

🧪 Blood Tests:

📄 Genetic Report:


Frequently Asked Questions About Antioxidants and NQO1 rs1800566

How does the NQO1 rs1800566 genotype affect my antioxidant defense?

The NQO1 gene helps detoxify reactive compounds and recycle fat-soluble antioxidants like vitamin E and coenzyme Q10. Variations in NQO1 can change enzyme efficiency, which may influence how well your body handles oxidative stress from everyday exposures such as pollution, smoking, poor diet, and stress.

What lifestyle and diet priorities should I follow if my NQO1 activity is reduced?

If your rs1800566 genotype is associated with reduced NQO1 activity, focusing on antioxidant support can be especially important. Emphasize a colorful, plant-rich diet (fruits, vegetables, polyphenol sources), include healthy fats for absorption of fat-soluble antioxidants, avoid smoking, limit pollution/secondhand smoke, manage stress, and prioritize regular moderate exercise and quality sleep.

What tests can help tailor an antioxidant-focused plan for my NQO1 genotype?

When there are concerns about nutrient status or oxidative stress, your healthcare provider may recommend blood tests such as vitamin C and vitamin E levels and coenzyme Q10, along with markers of inflammation or standard metabolic panels. PlexusDx commonly pairs genetic insights with reports like the Diet and Nutrition Genetic Report and may use related options such as the Precision Functional Health Genetic Test or Precision Diet and Weight Loss Genetic Test to inform education and next steps.

What tests can help me learn more about Antioxidants and NQO1 rs1800566?

The Optimal Diet and Weight Loss Genetic Test delivers over 295 genetic insights related to nutrition response, body composition, metabolism, and fitness. The Diet and Nutrition Genetic Report translates your results into personalized, actionable guidance. Your healthcare provider can also recommend targeted blood tests based on your specific pathway results and health history to complement your genetic insights with current biomarker data.


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.