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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.

Manganese, Iron, and Your HFE Gene: What Your Genotype May Mean for Mineral Balance

Manganese is an essential trace mineral that supports bone development, energy metabolism, and antioxidant defenses. Your body carefully balances manganese alongside other minerals, especially iron. The HFE gene helps regulate iron absorption, and certain HFE variants can change how much iron your body takes up. Because iron and manganese share absorption pathways in the intestine, changes in iron absorption can influence manganese levels.

This article explains how common HFE variation at rs1799945 can affect iron and manganese balance, practical diet and lifestyle steps to support healthy mineral levels, and what to discuss with your healthcare provider. PlexusDx provides educational information about genetic predispositions only and does not provide medical advice. Always consult your healthcare provider before making changes to supplements, medications, or major lifestyle patterns.

How HFE, Iron, and Manganese Interact

The HFE gene helps control how much dietary iron your intestines absorb. The rs1799945 variant (sometimes described by alleles C and G) can alter that control. When HFE increases iron absorption, iron stores in the body (commonly measured as ferritin) may rise. Because iron and manganese use overlapping transport systems in the gut, higher iron uptake can reduce manganese absorption and lower manganese levels in the blood.

Manganese plays roles in: bone formation, energy metabolism (as a cofactor for enzymes), antioxidant defense, and connective tissue formation. Low manganese can impair these processes, while high iron stores can have other health effects. The goal is balanced mineral status through diet, lifestyle, and targeted testing when needed.

Diet, Supplements, and Lifestyle Recommendations

  • Eat a varied diet emphasizing vegetables, fruits, whole grains, legumes, nuts, and lean proteins to supply a range of vitamins and minerals, including manganese.
  • Moderate intake of red and processed meats. These foods are high in heme iron, which is absorbed efficiently and can raise iron stores.
  • Avoid excessive use of iron-fortified foods and over-the-counter iron supplements unless a healthcare provider advises them based on blood tests.
  • Include foods that naturally reduce iron absorption when appropriate. For example, phytate-containing whole grains and legumes, and calcium-rich foods taken with iron-containing meals, can modestly lower iron uptake.
  • Limit alcohol consumption. Alcohol can increase iron absorption and worsen iron overload risk in susceptible individuals.
  • Ensure dietary sources of manganese: whole grains, nuts (especially almonds and pecans), legumes, leafy green vegetables, and tea. Manganese also occurs in small amounts in many other plant foods.
  • Use supplements cautiously. If testing suggests low manganese, a provider can recommend an appropriate dose. Avoid taking supplemental iron unless clinically indicated, particularly if you carry HFE variants associated with higher iron absorption.
  • Consider spacing minerals. If taking both iron and manganese supplements, take them at different times of day to reduce competition for absorption.
  • Monitor overall nutrient status. Maintain adequate intake of vitamin C, which increases non-heme iron absorption, and be mindful of interactions between nutrients that affect mineral uptake.

When to Consider Blood Tests and Professional Guidance

  • Ask your healthcare provider about testing ferritin and serum iron if you know you carry HFE variants or have symptoms suggestive of iron overload (fatigue, joint pain, unexplained abdominal pain, or abnormal liver tests).
  • If ferritin is elevated, providers may evaluate for iron overload and recommend follow-up testing, periodic monitoring, or interventions such as therapeutic phlebotomy when indicated.
  • If you are concerned about manganese status due to symptoms or risk factors, a provider can order specific tests and suggest dietary or supplemental strategies tailored to your situation.
  • Genetic results are one piece of the picture. Clinical context, blood tests, medications, other health conditions, and diet all determine management decisions.

Genetic Interpretations

2 effect alleles (GG genotype)

You have two copies of the effect allele at rs1799945 (GG). This genotype is associated with increased iron absorption and possibly higher ferritin levels, meaning greater iron stores in the body. Because iron and manganese share intestinal transport pathways, higher iron uptake may lead to reduced serum manganese levels.

Practical points:

  • Consider limiting intake of iron-rich and iron-fortified foods unless a provider advises otherwise.
  • Moderate alcohol and reduce red and processed meat intake to avoid further increases in iron stores.
  • Favor manganese-containing plant foods such as whole grains, nuts, legumes, and leafy greens to support manganese intake.
  • Discuss ferritin and iron studies with your healthcare provider to confirm iron status and guide any needed interventions.
1 effect allele (CG genotype)

You carry one copy of the effect allele at rs1799945 (CG). This genotype may be associated with modestly increased iron absorption and likely lower serum manganese levels compared with people without the effect allele. The impact is generally intermediate between the two-copy and zero-copy states.

Practical points:

  • Adopt a balanced diet with varied plant foods to maintain manganese intake.
  • Monitor red meat, fortified foods, and supplemental iron; avoid unnecessary iron supplementation unless testing indicates deficiency.
  • Limit alcohol and be mindful of factors that increase iron absorption, such as taking vitamin C with iron-rich meals.
  • Talk with your healthcare provider about baseline ferritin testing if there is concern about iron stores or symptoms related to mineral imbalance.
0 effect alleles (CC genotype)

You have two copies of the non-effect allele at rs1799945 (CC). This genotype is associated with typical HFE function and standard regulation of iron absorption. Your iron and manganese absorption pathways are likely to behave as expected for the general population.

Practical points:

  • Maintain a varied, nutrient-dense diet including vegetables, fruits, whole grains, legumes, lean proteins, and nuts.
  • No special modification related to HFE variation is necessary, but general recommendations for balanced mineral intake still apply.
  • If you have symptoms or other risk factors for mineral imbalance, discuss testing with your healthcare provider as needed.

Final Notes

Genetic variation at HFE is one factor that can influence how your body manages iron and manganese, but it does not determine your health on its own. Diet, lifestyle, existing health conditions, medications, and other genes all contribute to nutrient status and risk. PlexusDx provides educational genetic information only and does not provide medical advice. Always consult your healthcare provider to interpret genetic results in the context of your health history, to order appropriate blood tests, and to develop a personalized plan for nutrition, supplements, 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 Manganese and HFE rs1799945

How does the HFE rs1799945 variant affect iron absorption and ferritin levels?

The HFE gene helps regulate how much dietary iron your intestines absorb. The rs1799945 variant can alter this control, and the “effect” allele is associated with increased iron absorption, which may raise iron stores commonly measured as ferritin. The magnitude of this effect can vary by genotype (CC typical regulation, CG intermediate, GG increased iron absorption and possibly higher ferritin).

Why can changes in iron absorption also change manganese levels?

Iron and manganese share overlapping absorption/transport pathways in the intestine. When HFE-related genetics increase iron uptake, it can reduce manganese absorption, potentially lowering serum manganese levels. This interplay matters because manganese supports bone development, energy metabolism, antioxidant defenses, and connective tissue formation, so imbalance may affect multiple body functions.

What diet and supplement steps can support balanced iron and manganese—especially if I carry the rs1799945 effect allele?

Focus on a varied, nutrient-dense diet that includes whole grains, legumes, nuts, fruits, vegetables, and lean proteins to support manganese intake, while moderating red and processed meat to help manage iron stores. Avoid excessive iron-fortified foods and don’t take over-the-counter iron supplements unless guided by blood tests. If concern exists for mineral imbalance, consider discussing ferritin and serum iron testing with your healthcare provider; if you use both iron and manganese supplements, spacing them out may reduce absorption competition. Alcohol should be limited since it can increase iron absorption in susceptible individuals.

What tests can help me learn more about Manganese and HFE rs1799945?

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.