New Research Links Fermented Foods to Lower Systemic Inflammation

Using data from the Korea National Health and Nutrition Examination Survey (KNHANES), researchers at Tufts University investigated the relationship between the intake of foods containing live microbes—such as yogurt and kimchi—and various health indicators.¹ Published in the Journal of Nutrition in February 2026, the cross-sectional study, “Associations between Live Dietary Microbe Intake and Cardiometabolic Health in Korean Adults,” examined a comprehensive survey of live microbe consumption and its impact on cardiometabolic health indicators. More research on the potential health benefits, including gut microbiome composition and immune function, of live microbe consumption beyond probiotics is needed, the researchers state. The research was supported by Institute for the Advancement of Food and Nutrition Sciences (IAFNS) Nutrition for Gut Health Committee.

Study Details and Significance

The researchers developed a KNHANES-based system of classifying live microbes and developed food codes that overlapped with U.S. National Health and Nutrition Examination Survey (NHANES, 2001–2018). The cardiometabolic health outcomes included cholesterols, triglycerides, blood pressure, fasting blood sugar, C-reactive protein (CRP), and waist circumference.

Previous NHANES analysis has indicated that higher live microbe consumption has been associated with lower CRP concentrations and a more favorable lipid profile, the study explains, noting that analysis in regional-specific populations on this topic is still needed. For example, this study found that 2.2% of KNHANES participants were classified as nonconsumers of medium- or high-microbe containing foods, compared to 36% of adults in the NHANES.

Study Results: Kimchi and CRP

The study found a significant correlation between higher consumption of kimchi foods and reduced CRP, thought the results should be interpreted with caution, the researchers stated, due to potential effects from nonmicrobial aspects of kimchi and with overall dietary patterns. No correlation was seen between total live microbe intake and CRP concentrations. A statistically significant correlation in total cholesterol was also seen, though it was not large enough to be clinically significant. No associations were seen between the other health outcomes.

Traditional Korean dishes contain a variety of fermented foods and beverages, the researchers also noted. “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,” explained senior author Dr. Mei Chung, Associate Professor at the Friedman School of Nutrition Science and Policy at Tufts University, in a news release from IAFNS.²

This study was the first to quantify live microbe intake in a nationally representative Korean population and its association with cardiometabolic outcomes, offering new data on the subject. By quantifying live microbe intake across a large population, this study provides a potential scientific foundation for future dietary recommendations. “By incorporating comprehensive dietary adjustments or examining nutrient–nutrient and intake-age groups interactions, 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,” the researchers also concluded.

Advancing Protein Quality Testing: Moving Beyond Animal Models

IAFNS, specifically its Protein Committee, also recently supported a nine-laboratory study aimed at offering alternatives to how protein digestibility is measured.³ “A collaborative study to validate in vitro assays for protein digestibility assessment using pH-drop and pH-stat methods,” was published in the Journal of Food Composition and Analysis in January 2026.⁴ As new protein sources enter food formulations, the industry faces a hurdle: traditional protein quality assessments rely on animal testing (rodent bioassays), which are not only time-consuming and expensive but also raise increasing ethical concerns, the study explains. Additionally, to evaluate protein quality, North American food labeling regulations require animal-based protein digestibility correction factors, though for alternative and plant-based protein companies this presents an ethical dilemma, the news release from IAFNS notes.

The new study validated two methods: the pH-drop and pH-stat assays. These tests simulate human digestion by measuring how quickly proteins break down into amino acids. The multi-lab collaboration proved that these animal-free methods are highly repeatable and reproducible across different facilities.

"This work is critical for the ability for industry and consumers to adapt to changing food systems and dietary patterns by, hopefully, expediting protein quality assessments,” Chris Marinangeli from Protein Industries Canada explained. “Also, there are always opportunities for regulatory agencies to adopt new and validated methods that reduce regulatory burden.”

This article was created with assistance from AI. The content has been reviewed and edited by Erin McEvoy, Associate Editor. For more information on the extent and nature of AI usage, please contact us.

References

1. Zhao N, Zhan Y, Choi J, Lee HJ, Chung M. Associations between Live Dietary Microbe Intake and Cardiometabolic Health in Korean Adults. The Journal of Nutrition, 2026;101459. doi:10.1016/j.tjnut.2026.101459
2. Gibb S. Korean Live Microbes Survey Finds Less Inflammation from Consuming Fermented Foods. Published March 19, 2026. Accessed March 19. 2026. https://www.newswise.com/articles/korean-live-microbes-survey-finds-less-inflammation-from-consuming-fermented-foods
3. Institute for the Advancement of Food and Nutrition Sciences. Lab Studies Advance Protein Digestibility Tests for Food. Published March 16, 2026. Accessed March 19, 2026. https://www.newswise.com/articles/lab-studies-advance-protein-digestibility-tests-for-food-lab-studies-advance-protein-digestibility-tests-for-food
4. Goldberg EM, Sá AGA, Franczyk AJ, Krul ES, Lyle B, Jing M, et al. A collaborative study to validate in vitro assays for protein digestibility assessment using pH-drop and pH-stat methods, Journal of Food Composition and Analysis. 2026;151:108918. doi.org/10.1016/j.jfca.2026.108918.