HSA | FSA CARDS ARE NOW ACCEPTED

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.

Understanding Vitamin A and Your BCO1 Gene

Vitamin A is essential for healthy vision, immune function, cell growth, and skin health. It exists in two forms: preformed Vitamin A, found in animal foods such as eggs, dairy, and oily fish, and provitamin A carotenoids, like beta-carotene, found in colorful fruits and vegetables. The body converts beta-carotene into active Vitamin A using an enzyme produced by the BCO1 gene. Variations in the BCO1 gene can change how efficiently you convert plant-based beta-carotene into usable Vitamin A, which can influence dietary needs and choices.

How the BCO1 Variant Affects Beta-Carotene Conversion

The single nucleotide variant rs12934922 in BCO1 influences beta-carotene conversion efficiency. Depending on your genotype, your body may convert beta-carotene to active Vitamin A at typical, reduced, or likely reduced rates. Even when conversion is reduced, beta-carotene still provides antioxidant benefits, but you may need to emphasize direct sources of Vitamin A or adjust eating patterns to maintain optimal levels.

PlexusDx Disclaimer

PlexusDx provides educational information about genetic predispositions only and does not provide medical advice. Always consult with your healthcare provider before making changes to diet, supplements, or lifestyle based on genetic results.

Practical Recommendations for Supporting Vitamin A Status

Below are practical steps to support healthy Vitamin A levels based on how effectively your body converts beta-carotene. These suggestions cover food choices, meal patterns to improve absorption, supplement considerations, lifestyle tips, and monitoring ideas.

Dietary Tips

  • Include preformed Vitamin A sources regularly if conversion may be reduced: eggs, full fat or fortified dairy, liver (in moderation), and oily fish such as salmon and mackerel.
  • Keep eating beta-carotene-rich vegetables and fruits: carrots, sweet potatoes, pumpkin, spinach, kale, red peppers, mango, and cantaloupe.
  • Pair carotenoid-rich foods with healthy fats to improve absorption: olive oil, avocado, nuts, seeds, or a small serving of full fat dairy.
  • Cook vegetables lightly when appropriate. Gentle cooking can increase carotenoid bioavailability from plant foods.
  • For plant-forward diets, focus on a variety of colored produce to obtain a mix of carotenoids and other antioxidants.

Supplement Considerations

  • Fish oil or cod liver oil provide preformed Vitamin A along with omega-3 fats. Use caution with cod liver oil because it is high in Vitamin A; avoid excessive intake.
  • Multivitamins that contain preformed Vitamin A (retinol or retinyl esters) or a mixed carotenoid supplement can be helpful if dietary intake is low. Choose products with moderate amounts to avoid toxicity.
  • Carotenoid supplements such as beta-carotene may not fully compensate for reduced conversion in some genotypes. If you rely on supplements, consider formulations that contain preformed Vitamin A if conversion is a concern.
  • Do not exceed recommended upper limits for preformed Vitamin A. Chronic high intake of retinol can be toxic, particularly for pregnant people. Consult your healthcare provider for individualized dosing.

Lifestyle and Monitoring

  • Watch for visual changes, dry skin, or frequent infections as potential signs of low Vitamin A. These are not diagnostic and should prompt discussion with your healthcare provider.
  • Discuss routine blood testing with your clinician if you have concerns. Serum retinol or a broader nutritional panel can provide objective information about Vitamin A status.
  • Consider working with a registered dietitian or your primary care provider to match dietary changes or supplements to your overall health needs and medications.
  • Pregnancy planning requires careful attention to Vitamin A because too much preformed Vitamin A can cause birth defects. Always consult with your healthcare provider before taking Vitamin A supplements during pregnancy.

Genetic Interpretation

2 effect alleles (TT for rs12934922)

If you have the TT genotype, you carry two copies of the effect allele associated with decreased beta-carotene conversion to the active form of Vitamin A. Your BCO1 enzyme is less efficient at transforming beta-carotene from plant foods into usable Vitamin A. While beta-carotene still provides antioxidant benefits, relying on plant sources alone may not supply enough active Vitamin A for some biological needs.

Practical steps

  • Prioritize preformed Vitamin A from animal sources: eggs, dairy, and oily fish. Include these foods regularly.
  • Continue consuming colorful vegetables and pair them with healthy fats to improve absorption.
  • Consider low to moderate supplemental preformed Vitamin A if dietary intake is insufficient, after discussing with your healthcare provider.
  • Monitor vision, skin health, and immune function and consult your clinician about blood testing if you notice concerning symptoms.
1 effect allele (AT for rs12934922)

If you have the AT genotype, you carry one copy of the effect allele and one non-effect allele. This genotype is associated with likely decreased beta-carotene conversion compared with people with two non-effect alleles. Your body can still convert some beta-carotene, but at a lower efficiency than typical.

Practical steps

  • Include both plant and animal sources of Vitamin A. Aim for regular servings of eggs, dairy, or oily fish alongside lots of colorful produce.
  • Always eat carotenoid-rich foods with a source of healthy fat to maximize uptake.
  • If you follow a strict vegetarian or vegan diet, consider planning for alternative preformed Vitamin A sources or discuss supplements with your healthcare provider.
  • Monitor general signs of low Vitamin A and speak with your clinician about testing if needed.
0 effect alleles (AA for rs12934922)

If you have the AA genotype, you carry two copies of the non-effect allele associated with typical beta-carotene conversion efficiency. Your BCO1 enzyme likely converts beta-carotene from plant foods into active Vitamin A effectively, so you can obtain Vitamin A adequately from both plant-based and animal-based sources when your diet is balanced.

Practical steps

  • Maintain a balanced diet with colorful fruits and vegetables plus regular servings of eggs, dairy, or oily fish.
  • Pair carotenoid-rich foods with healthy fats to ensure good absorption.
  • Routine multivitamin use is optional if dietary intake is consistent. Avoid excessive preformed Vitamin A supplementation.

Next Steps and When to Talk to a Provider

If your genotype suggests reduced conversion, consider emphasizing preformed Vitamin A sources and absorption-enhancing meal patterns. Speak with your healthcare provider before starting any supplements. If you experience persistent vision changes, very dry skin, or frequent infections, consult your clinician for evaluation and possible testing.

PlexusDx provides educational information about genetic predispositions only and does not provide medical advice. Always consult your healthcare provider for personalized medical guidance and before making significant changes to your diet, supplement routine, or lifestyle.

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 Vitamin A and BCO1 rs12934922

How does the BCO1 rs12934922 variant affect my ability to use beta-carotene for Vitamin A?

The BCO1 rs12934922 variant can change how efficiently your body converts beta-carotene (from plant foods) into active Vitamin A. Depending on whether you have 0, 1, or 2 effect alleles, conversion may be typical or reduced. Even with reduced conversion, beta-carotene still supports antioxidant benefits, but you may need to emphasize preformed Vitamin A or adjust meal patterns to maintain optimal Vitamin A status.

What dietary changes should I consider if my genotype suggests decreased beta-carotene conversion?

If conversion is likely reduced, consider prioritizing preformed Vitamin A sources such as eggs, full-fat or fortified dairy, oily fish, and liver (in moderation). Continue eating colorful beta-carotene-rich produce like carrots, sweet potatoes, pumpkin, spinach, kale, red peppers, mango, and cantaloupe. To improve absorption, pair carotenoid-rich foods with healthy fats (olive oil, avocado, nuts, seeds, or some full-fat dairy) and lightly cook vegetables when appropriate.

When should I talk to a healthcare provider about Vitamin A supplements or testing?

Talk with your healthcare provider before starting supplements, especially if you rely on cod liver oil or any product containing preformed Vitamin A (retinol/retinyl esters), since high intake can be toxic. If you have concerns—such as persistent vision changes, very dry skin, or frequent infections—ask about objective testing (for example, serum retinol or a broader nutritional panel). If you’re pregnant or planning pregnancy, get medical guidance first because excess preformed Vitamin A can cause birth defects.

What tests can help me learn more about Vitamin A and BCO1 rs12934922?

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.