April 24, 2020
Otsuka Pharmaceutical Co., Ltd.
Research on the Relationship Between Hair Problems and Capacity to Produce Equol
Otsuka Pharmaceutical Co., Ltd. (head office: Tokyo, Japan; president and representative director: Makoto Inoue) is engaged in research into the bioactive compound equol, which is produced from soy isoflavones in the intestines. An observational study published in the journal of the Society of Aesthetic Dermatology, clarifies the relationship between the ability of postmenopausal women to produce equol and the density, softening and graying of their hair.
【Observational study on the relationship between hair and equol-producing status in postmenopausal women】
Otsuka researchers investigated the relationship between equol and hair in 200 Japanese postmenopausal women aged 45 to 64 years. All subjects were examined for their ability to produce equol in the intestine. We then investigated the relationship between each subject's equol-producing status and the number, density and diameter of hairs on the crown of their head, and on each subject's perceptions of their own hair. Equol is a component produced in the body by intestinal bacteria from soy isoflavones. Only one in two Japanese women are considered able to produce equol.
This study indicated that women who could not produce equol showed a decrease in hair density and an increase in thin hair, increasing with the number of months following after menopause. However, women who could produce equol showed no change in the density of regular hair and of vellus hair. In addition, women who produce equol showed fewer white hairs than those who could not produce equol. Women who could produce equol had positive perceptions of the "clumping, firmness and luster" of hair.
These findings suggest that equol may be involved in the control of hair aging (decrease in density, thinning, and graying) in postmenopausal women.
Equol has been proven to contribute to women's health in a wide variety of ways. The results of this study suggest new possibilities for equol and further research in the field of women's hair will be undertaken by Otsuka.
The Journal of Japanese Society of Aesthetic Dermatology Vol.30 No.1
Equol status affects hair aging in postmenopausal women: A cross-sectional study
Soh Iwashita, Haruna Miyakawa, Tomomi Ueno, Keisuke Hamamoto, Shigeto Uchiyama, Rie Ueki
Equol is a metabolite produced by the action of intestinal bacteria on the soy isoflavone daidzein. Produced in the intestine in response to the consumption of soy and similar in structure to estrogen, equol binds to estrogen receptors and functions weakly as the female sex hormone estrogen. Previously, soy isoflavones were thought to work similarly to female hormones, but the more research has progressed, the better it has become understood that it is equol metabolized from soy isoflavones that is key to supporting women's health and beauty rather than the soy isoflavones themselves. However, it is said that the percentage of women with the ability to produce equol is around 50 percent in countries where soy products are a regular part of the diet, such as Japan and China, and only 30 percent in America and Europe*, indicating that some women obtain no equol-derivable benefit from eating soy products. It has become possible to supplement the action of female hormones by ingesting foods that contain equol, supporting a healthy life regardless of whether or not the appropriate intestinal bacteria are present.
- Journal of Japan Society for Menopause and Women's Health, 20: 313-332, 2012
■Otsuka Pharmaceutical's Equol Research and Development
Otsuka has investigated the physical and psychological changes in menopausal women as part of its long-term research into soy. Since 1996, this research has been conducted by the Saga Nutraceuticals Research Institute and in 2002, the Institute succeeded in isolating the lactic acid bacteria strain Lactococcus 20-92 that produces equol. This lactic acid bacteria is used to ferment soy germ to produce equol for multiple research activities to investigate its safety and efficacy in both Japan and internationally.
Since Otsuka's 2014 launch in Japan of a nutritional product that has made equol easily accessible, medical professionals have cooperated in providing information and maintaining and promoting the health and quality of life of women who have begun to experience psychological and physical changes arising from menopause.
Information in this news release was current as of the original release date.