Medical Bulletin 07/ May/ 2024

In a groundbreaking randomized, double-blind clinical trial, researchers discovered evidence supporting the efficacy of Doenjang, a traditional Korean fermented food, in relieving symptoms of menopausal syndrome and combating obesity.

The study, published in the journal Nutrients, sheds light on the potential health benefits of this ancient culinary staple.

Menopause brings hormonal changes and various physical and psychological symptoms like hot flashes, insomnia, and anxiety. Doenjang, a traditional Korean soybean paste, contains compounds with hormone-like and antioxidant properties. These include isoflavones, saponins, phytic acid, and phytosterols, which may alleviate discomfort and reduce oxidative damage associated with menopause.

In a double-blind, randomized clinical trial, 62 postmenopausal women aged over 40 received Doenjang supplementation with a Kupperman index score of ≥15, which is widely used as a diagnostic criterion for menopausal syndrome. Researchers explored the effects of Doenjang with varying levels of beneficial microbial strains and compared them to commercially available Doenjang. They assessed the alleviation of menopausal syndrome, anti-obesity, and lipid-lowering benefits across the three groups. Additionally, they examined microbial changes in stool samples after Doenjang ingestion.

The study revealed a notable reduction in the mean Kupperman index after Doenjang consumption, with significant differences observed among the three groups. While the degree of decrease varied for each item across the groups, no scores increased following supplementation.

However, Doenjang did not exhibit anti-obesity, anti-inflammatory, or insulin resistance improvement effects. Nevertheless, it effectively lowered LDL cholesterol levels in the HDC and LDC groups. Moreover, after supplementation, the numbers of beneficial bacteria increased in all three groups, while harmful bacteria decreased only in the CD group.

In conclusion, traditional Doenjang is more effective in easing menopausal syndrome than commercial Doenjang. Although, there is a need for further research on the anti-obesity effect or changes in microbiomes and short-chain fatty acids in feces.

"Our findings highlight the potential of Doenjang as a natural remedy for menopausal symptoms and obesity management," the researchers wrote.

Reference: Han, A. L., Ryu, M. S., Yang, H., Jeong, D., & Choi, K. H. (2023). Evaluation of Menopausal Syndrome Relief and Anti-Obesity Efficacy of the Korean Fermented Food Doenjang: A Randomized, Double-Blind Clinical Trial. Nutrients, 16(8), 1194. https://doi.org/10.3390/nu16081194

According to a new study by Weill Cornell Medicine investigators, Inulin, a type of fibre found in certain plant-based foods and fibre supplements, causes inflammation in the gut and exacerbates inflammatory bowel disease.

The study, published in the Journal of Experimental Medicine, showed that inulin, which is found in foods like garlic, and leeks, as well as commonly used fibre supplements and foods with added fibre, stimulates microbes in the gut to release bile acids that increase the production of molecules that promote intestinal inflammation.

Dietary fiber, including inulin, is considered an essential part of a healthy diet for most people. Gut microbes turn inulin and other types of dietary fiber into short-chain fatty acids that turn on immune cells called regulatory T cells, which help reduce inflammation and have other beneficial effects throughout the body.

One such protein, called IL-33, causes immune cells called group 2 innate lymphoid cells (ILC2s) to become activated, triggering an excessive immune response similar to an allergic reaction. That excessive immune response then exacerbates intestinal damage and symptoms in an animal model of inflammatory bowel disease.

In the study, feeding inulin to mice in the model of inflammatory bowel disease increased the production of certain bile acids by specific groups of gut bacteria. The increased bile acids boosted the production of an inflammatory protein called IL-5 by ILC2s. In response to these changes, the immune system promotes the production of immune cells called eosinophils, which further ramp up inflammation and tissue damage. However, in the inflammatory bowel disease model, this chain reaction exacerbated intestinal inflammation, weight loss and other symptoms like diarrhea.

This analysis revealed that patients with inflammatory bowel disease, like the mice fed inulin, had higher levels of bile acids in their blood and stool and excessive levels of eosinophils in their intestine compared with people without the condition.

The results suggested that the inflammation cascade similar to that in the mice fed inulin is already primed in humans with inflammatory bowel disease, and dietary uptake of inulin may further exacerbate the disease.

Reference: Arifuzzaman, M., et al. (2024). Dietary fiber is a critical determinant of pathologic ILC2 responses and intestinal inflammation. The Journal of Experimental Medicine. doi.org/10.1084/jem.20232148.

A study presented at the European Society of Clinical Microbiology and Infectious Diseases conference revealed that over a third of patients treated with a precision approach to post-infectious irritable bowel syndrome (IBS) reported improved symptoms 12 weeks after starting treatment.

IBS is a chronic condition that affects a person’s digestive system. Symptoms include recurrent pain, changes to bowel habits.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by symptoms such as abdominal pain, bloating, gas, diarrhea, and constipation. It is a chronic condition that affects the large intestine and can significantly impact a person's quality of life. While the exact cause of IBS is not fully understood, it is believed to involve a combination of factors including abnormal gastrointestinal motility, increased sensitivity to certain foods, stress, and alterations in the gut microbiota.

In the study, researchers recruited 13 participants and prescribed a specific regime of one of two antibiotics to treat pathogenic bacteria that existed at levels that were too high, as well as probiotics to replace beneficial strains that were at levels that were too low. Prebiotics including inulin and psyllium were prescribed to over two thirds of participants.

After 12 weeks of treatment initiation, 12 out of 13 participants showed symptom improvement. Initially reported symptoms included abdominal pain, bloating, diarrhea, constipation, weight loss, and dyspepsia. Following treatment, the predominant symptoms were abdominal pain, bloating, and diarrhea. Additionally, five participants achieved complete symptom remission.

“As there is significant variation between even healthy individuals’ microbiome, it was unclear whether the dysbiosis — the imbalance between different bacterial strains in the gut — that occurs in people with post-infectious IBS had caused the symptoms they experienced. People should have their microbiome sequenced when they are healthy in order for research in this area to advance, and causal factors to be identified. If we can get to that stage, I think we will truly practise personalized medicine, and we can get much better in targeting treatments with some of these antibiotics, probiotics or prebiotics,” explained Satish Rao, gastroenterologist and professor of medicine at the Medical College of Georgia, Augusta University.

Reference: European Society of Clinical Microbiology and Infectious Diseases conference: Barcelona, Spain- 27-30 April; Can a personalized antibiotics, prebiotics, and probiotics combo help treat IBS?