Lactobacillus gasseri CP2305 Alleviates Premenstrual Depressed Mood and Anxiety in Women
~ Paraprobiotics that support women from the gut to maintain their mental and physical health ~
Before menstruation, women may experience mental symptoms in addition to physical symptoms, such as swelling and breast tension. This is due to changes in the balance of hormone levels in the premenstrual period, and reportedly, more than 90% of women experience these symptoms (※1). The Asahi Group has found that heat-killed Lactobacillus gasseri CP2305 (＊1), a microorganism strain, has the potential to improve premenstrual symptoms, such as depressed mood and anxiety. This is the first report on the discovery of a paraprobiotic (＊2) that reduces premenstrual symptoms in women.
● Intake of heat-killed Lactobacillus gasseri CP2305 alleviated depressed mood, anxiety, lethargy, fatigability, and sleepiness among premenstrual symptoms in women.
● Lactobacillus gasseri CP2305 acts on the secretion of female hormones, such as estradiol (＊3) and progesterone (＊4), during the luteal phase, which may alleviate premenstrual psychological symptoms.
● Paraprobiotic Lactobacillus gasseri CP2305 is effective in relieving premenstrual symptoms.
The link between the mind and the body in women seems to become unsteady due to cyclical hormonal changes. Thus, we have been conducting research focusing on interrelation among the gut microbes, the gut, and the mind. In this study, we demonstrated that Lactobacillus gasseri CP2305, a strain of a type of lactobacillus whose safety in humans has been verified, is effective during the mentally unstable premenstrual period. We hope that more people will recognize paraprobiotics as an ingredient of a lifestyle habit that enables a positive approach to daily life. We will continue studying the interrelationship between the human mind and symbiotic microorganisms.
The symptoms that women experience before menstruation vary greatly from person to person, and the mechanism of such symptoms is still not fully understood. This study found that the intake of Lactobacillus gasseri CP2305 improves symptoms such as depressed mood and anxiety before menstruation, indicating the possibility of an approach to improve such psychological symptoms from the gut. Human bodies have regulation systems to maintain the body’s homeostasis, including fluctuations in female hormones. It is becoming clear that the function of the gut microflora, also known as the “forgotten organ,” is also involved in such regulation systems. We hope that the use of health-improving materials that work on the body from the gut, such as Lactobacillus gasseri CP2305, helps spread the concept of approaching one's overall physical and mental health from the intestines.
Women may experience symptoms, such as swelling, breast tension, excessive sleepiness, irritability, and depressed mood, about 3 to 10 days before menstruation. It has been known that these symptoms are caused by a decrease in the secretion of female hormones, such as estrogen (＊3) and progesterone (＊4), during the luteal phase of the menstrual cycle (see the Figure 1) (※3). These premenstrual symptoms, which are seemingly experienced by 90% of women, are considered to be a factor that lowers the QOL of women.
Lactobacillus gasseri CP2305, which has been studied by the Asahi Group for many years, was found to act on the intestines and relieve mental stress by acting on the brain via brain-gut interaction (＊5) (※2). As the secretion of female hormones is regulated by commands from the brain, the Asahi Group, in collaboration with Tokushima University, conducted a study on women, based on a hypothesis that Lactobacillus gasseri CP2305, which acts via brain-gut interaction, may also be effective in improving premenstrual mental symptoms. An evaluation of the effects of Lactobacillus gasseri CP2305 intake revealed that it acts on the secretion of female hormones and improves premenstrual mental symptoms. The results of this research may contribute to improving the QOL of women in their daily lives, and further studies are expected.
Seventy-five healthy female students between the ages of 20 and 35 were divided into two groups: one group received tablets containing heat-killed Lactobacillus gasseri CP2305 and the other group received a placebo (tablets without Lactobacillus gasseri CP2305) for six menstrual cycles. Premenstrual psychological symptoms were assessed at each cycle using a validated questionnaire. Hormone levels in saliva were also measured.
Figure 2. Alleviation of premenstrual psychological symptoms by intake of Lactobacillus gasseri CP2305 (Left) Change in depressed mood score; (Right) Change in anxious score (Adapted from the original paper)
■ Using a questionnaire, the Lactobacillus gasseri CP2305 intake group and the placebo group were asked about the status and degree of 12 main symptoms of premenstrual symptoms (depressed mood, anxiety, mood swings, irritability, lethargy, lack of concentration, fatigability, overeating, sleepiness, insomnia, distraction, and physical aspects). In the results, the Lactobacillus gasseri CP2305 intake group scored significantly lower than the placebo group in the categories of depressed mood, anxiety, lethargy, fatigability, and sleepiness. These results indicate that Lactobacillus gasseri CP2305 is effective in improving psychological symptoms among premenstrual symptoms.
■ For physical scores, there was no change in the Lactobacillus gasseri CP2305 intake group, while the scores decreased in the placebo group.
We collected saliva from the participant during the premenstrual period (luteal phase) and measured the concentrations of estradiol and progesterone (female hormones). Based on the results, it is confirmed that the ingestion of Lactobacillus gasseri CP2305 has effects on estradiol and progesterone during the luteal phase. This suggests that the intake of Lactobacillus gasseri CP2305 may relieve premenstrual symptoms by acting on the secretion of female hormones.
This study showed that Lactobacillus gasseri CP2305 has the possibility to alleviate premenstrual symptoms, such as depressed mood, anxiety, lethargy, fatigability, and sleepiness in women, as well as to relieve premenstrual psychological symptoms by acting on the secretion of estradiol and progesterone (female hormones). This is the first report of paraprobiotics that improve premenstrual symptoms in women, and application of this strain is expected to be useful. We hope to continue research on women's mental health so that we can contribute to the empowerment of women as well as to the maintenance and promotion of mental health for all people.
The research was conducted by the Core Technology Laboratories of Asahi Quality & Innovations, Ltd. (Head Office: Ibaraki, President: Manabu Sami), an affiliate of Asahi Group Holdings, Ltd. (Head Office: Tokyo, President: Atsushi Katsuki), in collaboration with Associate Professor Kensei Nishida from Tokushima University Graduate School of Biomedical Sciences (Medical Science). The results of the study were reported in a paper published in the Journal of Functional Foods, an international scientific journal, on March 21, 2021. Asahi Quality & Innovations will continue working on research and development to provide excellent health materials and support the health maintenance of our customers.
＊1. Lactobacillus gasseri CP2305
This strain was selected from the many lactic acid bacteria owned by the Asahi Group with the expectation that it may work through the mechanism of “brain-gut interaction” (＊5).
The strain has been reported to have beneficial effects on bowel control, stress relief, and sleep quality improvement.
＊2. Paraprobiotics
Non-viable microbial cells or cell components that have been sterilized with heat treatment, etc. and have the benefit of improving biological functions.
＊3. Estrogen and estradiol
Estrogen: A female hormone. The amount of secretion increases between menstruation and ovulation and acts on the uterus to thicken the endometrium, which serves as a bed for fertilized eggs.
Estradiol: A type of estrogen and the main estrogen produced by the ovaries before menopause.
＊4. Progesterone
A female hormone. The amount of secretion increases between ovulation and the next menstruation, raising the basal body temperature and stabilizing the endometrium to facilitate the implant of fertilized eggs.
＊5. Brain-gut interaction
The gut and the brain communicate with each other to maintain biological functions. This mechanism is called “brain-gut interaction.”
○※1 T. Takeda et al. Prevalence of premenstrual syndrome and premenstrual dysphoric disorder in Japanese women, Archives of Women’s Mental Health, 9 (4) (2006), pp. 209-212,
10.1007/s00737-006-0137-9
○※2 D. Sawada et al. Daily intake of Lactobacillus gasseri CP2305 improves mental, physical, and sleep quality among Japanese medical students enrolled in a cadaver dissection course
, Journal of Functional Foods, 31 (2017), pp. 188-197, 10.1016/j.jff.2017.01.042
○※3 Japan Society of Obstetrics and Gynecology, Premenstual Syndrome (in Japanese)
http://www.jsog.or.jp/modules/diseases/index.php?content_id=13
