Which tests measure 2-Hydroxyestrone : 4-Hydroxyestrone Ratio?

2-Hydroxyestrone : 4-Hydroxyestrone Ratio is measured in 1 test on BiomarkersLabs.com, including Essential Estrogens™ - 24 hr.

Biomarker Reference · 2:4 Ratio

What does the 2-Hydroxyestrone : 4-Hydroxyestrone Ratio test measure?

Q: What is the reference range for 2-Hydroxyestrone : 4-Hydroxyestrone Ratio?

The standard reference range for 2-Hydroxyestrone : 4-Hydroxyestrone Ratio is Typically >5; higher values considered more favourable; method- and laboratory-specific.. Reference ranges vary by laboratory and assay platform — interpret in context of the issuing laboratory's stated range.

2-Hydroxyestrone : 4-Hydroxyestrone Ratio (2:4 Ratio) is a clinical biomarker used in female-hormones assessment. This ratio compares the flux through the 'protective' 2-hydroxylation pathway with the genotoxic 4-pathway. It is measured in 1 laboratory test on BiomarkersLabs.com.

Reference Range: Typically >5; higher values considered more favourable; method- and laboratory-specific.
Units: ratio
Measured In: 1 test
Category: Female Hormones

Functional medicine optimalFunctional targets often aim for a 2:4 ratio above 5–10, though this is an exploratory marker without validated clinical thresholds.

What is 2-Hydroxyestrone : 4-Hydroxyestrone Ratio?

This ratio compares the flux through the 'protective' 2-hydroxylation pathway with the genotoxic 4-pathway. A higher ratio indicates preferential metabolism toward 2-OHE1, reducing formation of DNA-damaging 4-hydroxy quinones. The ratio is influenced by CYP1A1, CYP1B1 polymorphisms, cruciferous vegetable intake, and body composition.

Why is 2-Hydroxyestrone : 4-Hydroxyestrone Ratio measured?

The 2:4 ratio is used in functional and integrative oncology as a modifiable biomarker of oestrogen metabolism safety. Interventions to raise the ratio include indole-3-carbinol or diindolylmethane supplementation, weight loss, and cruciferous vegetable consumption, though randomised data linking ratio changes to cancer outcomes are lacking.

Reference ranges

Standard reference: Typically >5; higher values considered more favourable; method- and laboratory-specific.
Functional medicine optimal: Functional targets often aim for a 2:4 ratio above 5–10, though this is an exploratory marker without validated clinical thresholds.
Units: ratio

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.

Tests that measure 2-Hydroxyestrone : 4-Hydroxyestrone Ratio

1 test on BiomarkersLabs.com include this biomarker.

BML-HRF-025Comprehensive

Essential Estrogens™ - 24 hr

2-Hydroxyestrone : 4-Hydroxyestrone Ratio reference range in this test: Typically >5; higher values considered more favourable; method- and laboratory-specific.

Related clinical conditions

Related Biomarkers

Frequently measured alongside

EstroneE15 tests EstradiolE25 tests EstriolE35 tests 2-Hydroxyestrone2-OHE14 tests 16α-Hydroxyestrone16α-OHE11 test 4-Hydroxyestrone4-OHE14 tests 2-Hydroxyestrone : 16α-Hydroxyestrone Ratio2:16α Ratio1 test

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