Kimchi bacteria flush nanoplastics from gut with added heart health benefits
Key takeaways
- The World Institute of Kimchi found strain CBA3656 from kimchi binds 57% of polystyrene nanoplastics in simulated human intestines, doubling fecal excretion in germ-free mice.
- South Korean national health data links higher kimchi or fermented food intake to lower systemic inflammation, with a minor total cholesterol uptick.
- Dual benefits position kimchi bacteria as potential public health tools for plastic pollution mitigation and inflammation reduction, though cross-sectional data limits causality claims.
The World Institute of Kimchi study has found that a lactic acid bacterium from kimchi can help remove nanoplastics from the body by binding them in the intestine. Meanwhile, another new study using South Korean health data has found that higher intake of fermented foods like kimchi is linked to lower systemic inflammation. Nutrition Insight examines these findings to uncover the benefits of the traditional side dish.
Funded by the Korean Ministry of Science and ICT, the World Institute of Kimchi found that the lactic acid bacterium, Leuconostoc mesenteroides CBA3656, in the dish acts against polystyrene nanoplastics (PS-NPs).
These plastic particles are under 1 μm and can cross the human body when drinking water or eating food and accumulate in organs, such as the kidney and brain. Biological strategies to remove nanoplastics in the gastrointestinal tract are still in their early stages.
“Plastic pollution is increasingly recognized not only as an environmental issue but also as a public health concern,” says study researcher Dr. Sehee Lee at the World Institute of Kimchi.
“Our findings suggest that microorganisms derived from traditional fermented foods could represent a new biological approach to address this emerging challenge.”
Lab and animal tests
The researchers say their Bioresource Technology study results imply that CBA3656 can stably bind nanoplastics in the intestine for fecal excretion. They observed this in artificial environments resembling the human intestinal tract.
Mechanism of nanoplastic biosorption by kimchi lactic acid bacteria (Image credit: World Institute of Kimchi).Along with her colleague Dr. Tae Woong Whon, Lee showed that strain CBA3656 has an adsorption efficiency of 87% in the laboratory, which is comparable to the reference strain Latilactobacillus sakei CBA3608 (85%).
However, under simulated human intestinal conditions, the adsorption rate of strain CBA3608 decreased to 3% while strain CBA3656 maintained a substantially higher adsorption level of 57%
In germ-free mice, the same findings were noted. Male and female mice who were given CBA3656 had over a twofold increase in nanoplastics detected in feces compared to the control group.
“We will continue to expand the scientific value of kimchi microbial resources to contribute to public health and environmental solutions,” comments Lee.
Previous World Institute of Kimchi research found that isolated lactic acid bacteria from kimchi had high levels of resistance to phages.
Kimchi linked to heart health
A separate study in the Journal of Nutrition examined whether microbe intake from fermented foods can be linked to lower systemic inflammation.
Supported by the Institute for the Advancement of Food and Nutrition Sciences, researchers employed data from the 2016–2020 South Korean National Health and Nutrition Examination Survey where commonly eaten and various types of kimchi were classified as being high in microbes.
Fermented foods like kimchi correlate with lower inflammation markers in Korean adults per national health data.The study shows an inverse association between live microbe intake from kimchi and C-reactive protein levels, which indicates systemic inflammation, although there was no significant association between total live microbe intake and C-reactive protein levels.
Additionally, there was a positive association with total cholesterol, but this was too small to be clinically significant. No other major associations were observed.
Strengths, weaknesses & future directions
The new study is the first to quantify live microbe intake in the South Korean population while linking it to positive cardiometabolic health outcomes. Despite kimchi being widely consumed, the study points out that its potential health effects in the Korean population have remained limited.
“Given the unique role of kimchi in the Korean diet, cross-cultural comparisons by pooling data to provide wider ranges of microbe and other nutrient intake that are linked to cardiometabolic health may provide valuable insights into the potential public health implications,” says senior author Dr. Mei Chung, associate professor at the Friedman School of Nutrition Science and Policy at Tufts University, US.
The study’s strength is touted to be the use of nationally representative data, systemic classification of live microbe intake, and survey-weighted models that help with complex sampling.
However, the researchers caution that the results should not be taken causally, as they were based on cross-sectional research. Instead, the findings can be attributed to the complexity of diet-health interactions, differences in individual microbial composition, and the potential influence of unmeasured factors like dietary patterns, lifestyle, or genetics.
“Future research can more accurately determine whether the observed health benefits are attributable to live microbes themselves or to broader dietary patterns associated with fermented food consumption,” they conclude.
A previous study suggested that consuming up to three daily servings of kimchi, including the popular radish kimchi, is associated with a reduced prevalence of obesity.
