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Published on: September 15, 2012
Equol production changes over time in pre-menopausal women
Adrian A Franke1, Jennifer F Lai, Ian Pagano
1University of Hawaii Cancer Center, Clinical Sciences Program, 1236 Lauhala Street, Honolulu, HI 96813, USA. adrian@cc.hawaii.edu
The British Journal of Nutrition
|September 17, 2011
Summary
Equol (EQ) production from daidzein (DE) by gut bacteria is not stable. Many individuals change their status as equol producers (EP) or non-producers (NP) over time, challenging previous assumptions.
Area of Science:
- Microbiome-metabolite interactions
- Nutritional biochemistry
- Human metabolism
Background:
- Equol (EQ) is a beneficial metabolite from soya isoflavone daidzein (DE), produced by gut bacteria.
- EQ production is typically considered a stable individual trait, varying between 30-60% of the population.
Purpose of the Study:
- To investigate the stability of equol (EQ) production in pre-menopausal women over time.
- To determine if dietary soya intake influences an individual's status as an EQ producer (EP) or non-producer (NP).
Main Methods:
- A randomized, cross-over study involving 79 pre-menopausal women.
- Participants consumed high-soya and low-soya diets for 6 months each, with a 1-month washout period.
- Urine samples were analyzed for daidzein (DE) and equol (EQ) using liquid chromatography tandem MS.
Main Results:
- 19% and 24% of women were EQ producers (EP) on low-soya and high-soya diets, respectively.
- 6-11% of subjects changed EQ status within diet periods, and 16% changed between diet periods.
- Individual EQ production status demonstrated significant variability over the study duration.
Conclusions:
- Equol (EQ) production is not a stable phenomenon within individuals.
- Dietary soya intake may influence EQ production status.
- Further research is needed to identify factors affecting EQ production variability.
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