Doenjang (fermented soybean paste), a traditional Korean seasoning ingredient, is believed to have health benefits for menopausal women through altering the composition of intestinal microorganisms and promoting better metabolism.
To compare the effect of traditionally made doenjang and commercially available doenjang on menopause symptoms, an eight-week randomised, double-blind clinical trial was conducted in South Korea.
The study was funded by the local Ministry of Agriculture, Food and Rural Affairs, and government agency Korea Agro-Fisheries & Food Trade Corporation (aT).
A total of 56 women between the ages of 45 and 70 who had passed 12 months since their last period, were clinically diagnosed with menopausal syndrome, and had a Kupperman index of 15 or above, were included in the final analysis.
The Kupperman index (KI) is a commonly used method to identify the severity and characteristics of menopausal symptoms. Scores of 20 or less are classified as mild, 20 to 40 points as moderate, and 40 to 60 points or higher as severe.
Doenjang is categorised based on the manufacturing process. Commercial doenjang (CD) is primarily fermented with kōji mould, whereas traditional doenjang is fermented with kōji mould and beneficial microorganisms like Bacillus subtilis.
Through a microbiome analysis, traditional doenjang is further classified into doenjang with a high content of “usable microorganisms” (HDC) and doenjang with low content of usable microorganisms (LDC).
In this trial, the doenjang was freeze-dried and crushed to make into tablets.
Participants were randomly assigned to take 6g of CD, HDC or LDC tablet twice a day.
Following the intervention, KI values improved and total scores significantly decreased in all three groups. In particular, total KI scores fell the most in the LDC group.
Among other symptoms that were investigated separately and not part of the KI, nervousness decreased in all three groups, melancholia in the LDC and CD groups, vertigo in the HDC group, and fatigue in the CD group.
Additionally, headache, palpitations, formication, and vaginal dryness improved in the HDC and LDC groups.
Increase in beneficial bacteria
The presence of microorganisms in the stool samples following doenjang tablet supplementation was assessed.
It was found that the number of beneficial bacteria (Bacteroidetes), including Lactobacillus spp., Bifidobacterium spp., Lactococcus lactis, Enterococcus faecium, and Bacteroides spp. increased in all three groups, and was statistically significant in only the HDC and CD groups.
On the other hand, the number of harmful bacteria (Firmicutes), including Clostridium perfringens, Bacteroides eggerthii, Sutterella stercoricanis, Ruminococcus torques, Parabacteroides merdae, and Parabacteroides distasonis significantly decreased only in the CD group.
The Firmicutes-to-Bacteroidetes (F/B) ratio, known to play an important part in maintaining gut homeostasis and is linked to obesity and inflammatory bowel disease, did not decrease in any of the three groups.
While doenjang supplementation did not show an effect on anti-obesity, anti-inflammatory or insulin resistance, it was effective in reducing the low-density lipoprotein (LDL) or “bad” cholesterol levels in the HDC and LDC groups.
“An increase in beneficial bacteria in the faeces, a hallmark of fermented foods, can be expected to improve the intestinal environment. The reduction in LDL cholesterol was found exclusively when using traditional doenjang, demonstrating its superiority. It also suggests protection against cardiovascular disease,” the researchers wrote.
According to the researchers, the consumption of fermented foods changes the gut microbiota and their metabolites, especially short-chain fatty acids (SCFAs).
“Although there is still no consensus on the mechanisms and roles of SCFAs in energy homeostasis, several studies have provided evidence of SCFAs as a possible treatment for diseases such as metabolic syndrome, obesity, and type 2 diabetes.
“Further research on the effect of doenjang on anti-obesity, or changes in microbiomes and SCFAs in faeces, is needed,” the researchers wrote.
Alternative treatment
Due to reported risks associated with hormonal therapy (HT), which used to be a widely treatment method before 2000, many women have attempted to overcome their menopause symptoms, such as hot flashes and vaginal dryness, by consuming various foods or functional products.
Fermented soybean products are said to have the potential to exert hormone-like activity and possess antioxidant properties.
For instance, doenjang contains antioxidants such as tocopherol, isoflavones, and phenolic acids derived from soybeans.
In particular, isoflavones bind strongly to oestrogen receptor beta (ERβ), predominant in the cardiovascular, genitourinary and skeletal systems, and can relieve menopausal symptoms through this mechanism of action.
Source: Nutrients
https://doi.org/10.3390/nu16081194
“Evaluation of Menopausal Syndrome Relief and Anti-Obesity Efficacy of the Korean Fermented Food Doenjang: A Randomized, Double-Blind Clinical Trial”
Authors: A Lum Han, et al
Women’s Health and Healthy Ageing will be key topics of focus at Growth Asia Summit 2024 – join us in Singapore to learn about market opportunities and glean insights from major industry experts. Find out more here.