4-OH-E1 % (Post-menopausal)

Optimal Result: 2 - 10 %.

Percentages of 2-OH-E1, 4-OH-E1, and 16-OH-E1

When evaluating phase I metabolism, it can be helpful to compare the percentages of 2, 4, and 16 OH-E1 metabolites. Most individuals metabolize the majority of their estrogens down the 2-OH-E1 pathway which is generally considered the “safer pathway”. This is followed by 16-OH-E1 and 4-OH-E1 respectively, both of which are deemed more reactive and potentially genotoxic.

What does it mean if your 4-OH-E1 % (Post-menopausal) result is too low?

4-OH E1 is associated with a higher risk of certain cancers and other markers for breast health in women. Low levels may be beneficial depending on the other metabolites and methylation further down the pathway.

What does it mean if your 4-OH-E1 % (Post-menopausal) result is too high?

Higher levels indicate slowed methylation and are associated with a higher risk for breast cancer in women. Elevation may also be due to an overactive CYP1B1 enzyme or sluggish CYP1A1 or CYP34A. Additional support for the COMT enzyme can help with the conversion toward the inactive metabolite, 4-M-E1.

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