Selenium | SEP15 (rs561104)

You carry two copies of the effect allele at rs561104 (CC). This genotype is associated with higher serum selenium compared to other variants. The SEP15 variation may change how efficiently selenium is incorporated into selenoproteins or how it is metabolized, leading to naturally elevated circulating selenium.

• Diet: Prioritize a balanced diet with selenium rich foods, but be cautious with extremely high sources. Good choices include seafood, lean meats, eggs, whole grains, and small amounts of Brazil nuts. Limit Brazil nuts to 1 to 2 nuts per day because they are very high in selenium.
• Supplements: Avoid routine selenium supplements unless a healthcare provider recommends them. With a genetic tendency toward higher serum selenium, supplementation increases the risk of exceeding safe levels.
• Lifestyle: Maintain a varied diet and avoid overreliance on fortified foods or multiple supplements that may contain selenium. Monitor any new supplements for selenium content.
• Blood testing: Consider discussing a serum or plasma selenium test with your provider if you regularly eat high selenium foods or take supplements, or if you have symptoms of excess selenium. Testing can clarify whether your levels are in a healthy range.
• When to seek care: Contact your clinician if you notice unexplained gastrointestinal symptoms, hair loss, brittle nails, or other changes that could suggest excessive selenium.

You carry one copy of the effect allele at rs561104 (CT). This genotype is associated with likely higher serum selenium levels relative to those without the effect allele. Your SEP15 variation may modestly increase the efficiency of selenium incorporation into selenoproteins or slow selenium clearance.

• Diet: Aim for balanced selenium intake from whole foods. Include seafood, poultry, eggs, beans, and grains. Limit Brazil nuts to 1 to 2 per day and avoid excessive intake.
• Supplements: Use selenium supplements only under medical advice. If your diet already provides good selenium, supplemental selenium may not be necessary and could risk exceeding safe limits.
• Lifestyle: Keep a food and supplement log for a short period if you are introducing new supplements or consuming Brazil nuts regularly. This helps estimate total selenium intake.
• Blood testing: Consider baseline serum selenium testing if you are concerned about high intake, use supplements, or have thyroid concerns. Repeat testing after diet or supplement changes if recommended by your provider.
• When to seek care: Report symptoms such as nausea, diarrhea, hair thinning, or nail changes to your clinician. These can be signs of excessive selenium and merit evaluation.

You carry two copies of the non-effect allele at rs561104 (TT). This genotype is associated with typical serum selenium levels, meaning your SEP15 variant does not appear to substantially alter selenium handling compared to the general population.

• Diet: Meet recommended selenium intake through diverse foods. Good sources include Brazil nuts in moderation, seafood, lean meats, eggs, and whole grains.
• Supplements: Most people with typical selenium status do not need supplements if they eat a varied diet. Consider supplementation only when advised by a healthcare professional, such as for diagnosed deficiency.
• Lifestyle: A diet rich in plant and animal sources along with routine health screenings supports balanced selenium levels and overall health.
• Blood testing: Test selenium if you have clinical concerns such as thyroid dysfunction, signs of deficiency, or if you follow a restricted diet that might limit selenium intake.
• When to seek care: Speak with your healthcare provider if you develop symptoms consistent with deficiency such as fatigue, muscle weakness, or thyroid-related changes.