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.

Choline, BHMT, and Your Health: What Your Genotype Means

Choline is an essential nutrient that supports brain function, liver health, nerve signaling, muscle movement, fat metabolism, and the body’s methylation processes. The BHMT gene makes an enzyme that helps convert choline into betaine. Betaine donates methyl groups used to process homocysteine, an amino acid that can pose health risks when elevated. Variations in BHMT can change how efficiently choline is converted into betaine and how well the BHMT pathway supports methylation.

How to Read This Report

The variant discussed here is rs3733890 in the BHMT gene. Below you will find plain-language interpretations for each possible genotype and practical, consumer-focused recommendations for diet, supplements, lifestyle, and testing to support healthy methylation and overall metabolic function.

Two effect alleles — AA (reduced BHMT activity)

What this means

If your genotype is AA, you carry two copies of the effect allele. This is associated with reduced BHMT enzyme activity. Less choline may be converted into betaine, so the BHMT route for processing homocysteine may be less efficient.

Practical implications

  • Your body may channel more choline toward CDP-choline (phosphatidylcholine) for cell membrane building and repair.
  • Folate supplementation alone may be less effective at lowering homocysteine for people with this genotype because the BHMT pathway is less active.
  • Supporting multiple methylation pathways is especially important.

Diet recommendations

  • Focus on choline-rich foods: egg yolks, liver (beef or chicken), salmon, shrimp, chicken, and soy products.
  • Include cruciferous vegetables: broccoli, Brussels sprouts, kale, and cauliflower.
  • Eat a balanced diet with quality protein, healthy fats, and whole grains to support overall methylation and liver health.

Supplement considerations

  • Consider a choline supplement if dietary intake is low. Options include choline bitartrate, phosphatidylcholine, or CDP-choline. Work with your provider on dose.
  • Support methylation with a B-complex that provides active forms: folate (5-MTHF), vitamin B12 (methylcobalamin), B6 (pyridoxal-5-phosphate), and riboflavin (B2).
  • Betaine (trimethylglycine) supplements may help boost methyl donor availability if diet alone is insufficient.

Lifestyle and monitoring

  • Limit excessive alcohol intake, which stresses the liver and methylation systems.
  • Maintain a healthy weight and regular physical activity to support liver function and metabolism.
  • Consider testing fasting homocysteine and liver function (ALT, AST) with your provider to monitor response to dietary and supplement changes.
One effect allele — AG (moderate influence)

What this means

If your genotype is AG, you carry one copy of the effect allele. This may moderately reduce BHMT enzyme efficiency. Your body might convert somewhat less choline into betaine compared to people with the GG genotype.

Practical implications

  • A moderate shift in choline use toward membrane-building pathways like CDP-choline may occur.
  • Folate alone may be somewhat less effective at lowering homocysteine, so multi-nutrient strategies are useful.

Diet recommendations

  • Include regular sources of choline: eggs, poultry, fish, soy, and cruciferous vegetables.
  • Eat a variety of fruits, vegetables, whole grains, and lean proteins to support overall methylation and antioxidant status.

Supplement considerations

  • A B-complex with active forms of folate and B12 can help cover key methylation cofactors.
  • If dietary choline is low, a choline supplement such as phosphatidylcholine or CDP-choline may be beneficial.

Lifestyle and monitoring

  • Exercise regularly and maintain healthy sleep patterns to support metabolic health.
  • Discuss with your provider whether homocysteine testing is appropriate for you, especially if you have other risk factors.
No effect alleles — GG (typical BHMT function)

What this means

If your genotype is GG, your BHMT enzyme function is expected to be typical. Your body efficiently converts choline into betaine and uses that pathway to help process homocysteine.

Practical implications

  • Your BHMT-mediated methylation capacity is likely functioning as expected.
  • Standard dietary and lifestyle measures to support methylation and liver health are appropriate.

Diet recommendations

  • Continue regular intake of choline-rich foods: egg yolks, liver, fish, chicken, and soy.
  • Include plenty of vegetables, particularly cruciferous types, to supply antioxidants and dietary fiber.

Supplement considerations

  • Most people with a balanced diet do not require targeted BHMT support, but a B-complex can be helpful during periods of high demand or limited nutrition.

Lifestyle and monitoring

  • Maintain healthy lifestyle habits: avoid excessive alcohol, stay active, manage stress, and aim for restorative sleep.
  • Routine provider-led bloodwork including lipid panel and metabolic markers is useful for overall health monitoring.

General Tips to Support Choline, Betaine, and Methylation

  • Eat a variety of whole foods: prioritize eggs, fish, lean meats, legumes, nuts, seeds, and cruciferous vegetables.
  • Balance your B vitamins: ensure adequate folate, B12, B6, and riboflavin through diet or a B-complex when needed.
  • Consider omega-3 rich foods like salmon and walnuts for brain and liver support.
  • Manage alcohol intake and avoid smoking to reduce stress on liver methylation pathways.
  • Stay hydrated, maintain a healthy weight, and engage in regular physical activity.

When to Talk to Your Healthcare Provider

  • If you have elevated homocysteine, liver disease, or a family history of cardiovascular or cognitive concerns, discuss targeted testing and personalized nutrient strategies.
  • If you are pregnant, breastfeeding, or planning pregnancy, discuss choline needs with your provider because choline is important for fetal brain development.
  • Before starting any supplements, especially high-dose B vitamins, betaine, or choline supplements, consult your healthcare provider to ensure safety and appropriate dosing.

PlexusDx does not provide medical advice. This information is educational and intended to help you understand genetic predispositions related to BHMT and choline metabolism. Always consult your healthcare provider before making changes to your diet, supplement routine, or medical care.

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 Choline and BHMT rs3733890

What does the BHMT rs3733890 variant mean for choline and methylation?

The BHMT rs3733890 variant affects how efficiently your body converts choline into betaine. Betaine then donates methyl groups used to help process homocysteine. Depending on whether you have two effect alleles (AA), one (AG), or none (GG), this BHMT pathway may be reduced, moderately impacted, or expected to function typically, which can influence methylation support and homocysteine processing.

How should my diet change if my rs3733890 genotype is AA or AG?

If you have AA (reduced BHMT activity) or AG (moderate influence), consider prioritizing choline-rich foods such as egg yolks, liver, salmon, shrimp, chicken, and soy products. Also include cruciferous vegetables (broccoli, Brussels sprouts, kale, cauliflower) to support antioxidant and fiber intake. Because folate alone may be less effective for reducing homocysteine when BHMT is less active, a multi-nutrient approach that supports multiple methylation cofactors may be especially important.

What supplements and labs are commonly considered for rs3733890?

Supplement options may include a choline supplement if dietary intake is low (such as choline bitartrate, phosphatidylcholine, or CDP-choline), and a B-complex using active forms like folate (5-MTHF), vitamin B12 (methylcobalamin), B6 (pyridoxal-5-phosphate), and riboflavin (B2). Betaine (trimethylglycine) may help if diet alone isn’t sufficient. Labs often discussed with a provider include fasting homocysteine and liver function tests (ALT, AST), and if relevant, other metabolic markers for overall monitoring—especially if you have elevated homocysteine or liver concerns.

What tests can help me learn more about Choline and BHMT rs3733890?

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.