Consumption Of Fermented Foods Research Articles

Dietary intake of yogurt and cheese in children at age 1 year and sleep duration at age 1 and 3 years: the Japan Environment and Children’s Study

BackgroundWe previously reported that 1-year-old infants born to mothers who regularly consumed fermented food during pregnancy had a lower risk of sleep deprivation. However, it is not known if these positive effects are enhanced when infants themselves eat fermented foods or the long-term effects of such consumption. In this study, we examined the association between the frequency of fermented food intake during the child’s weaning period and sleep deprivation at age 1 and 3 years.MethodsThis birth cohort study used data from a nationwide, government-funded study called the Japan Environment and Children’s Study (JECS), covering 65,210 mother-child pairs. We examined the association between infants’ consumption of fermented foods at 1 year of age and sleep deprivation at 1 and 3 years of age.ResultsThere was no association between yogurt or cheese intake and sleep duration at age 1; at age 3, there was no group difference, although a trend test showed that yogurt intake at age 1 was significantly associated with sleep duration at age 3. There was also no association between the frequency of cheese intake and inadequate sleep duration at age 3.ConclusionFrequency of children’s yogurt and cheese intake at age 1 was not associated with sleep duration at age 1 or 3. However, a trend test showed a significant association between the frequency of yogurt intake at age 1 and sleep duration at age 3.

Fermented foods and cardiometabolic health: Definitions, current evidence, and future perspectives.

Unhealthy diets contribute to the increasing burden of non-communicable diseases. Annually, over 11 million deaths worldwide are attributed to dietary risk factors, with the vast majority of deaths resulting from cardiometabolic diseases (CMDs) including cardiovascular disease (∼10 million) and type II diabetes (∼339,000). As such, defining diets and dietary patterns that mitigate CMD risk is of great public health importance. Recently, the consumption of fermented foods has emerged as an important dietary strategy for improving cardiometabolic health. Fermented foods have been present in the human diet for over 10,000 years, but knowledge on whether their consumption benefits human health, and the molecular and microbiological mechanisms underpinning their purported health benefits, is relatively nascent. This review provides an overview of the definitions of fermented foods, types and qualities of fermented foods consumed in Europe and globally, possible mechanisms between the consumption of fermented foods and cardiometabolic health, as well as the current state of the epidemiological evidence on fermented food intake and cardiometabolic health. Finally, we outline future perspectives and opportunities for improving the role of fermented foods in human diets.

Knowledge of fermentation and health benefits among general population in North-eastern Slovenia

BackgroundFermented foods are staples of the human diet and fermentation process has been used by humans for thousands of years. The preparation of fermented foods was performed in the past without knowledge of the role of microorganisms involved. Nowadays, fermented foods, due to their proclaimed health benefits for consumers, are becoming increasingly popular. Our study was constructed to provide data on awareness and use of fermented foods among people in North-eastern Slovenia.MethodsThe cross-sectional study included 349 individuals (16–89 years of age). An online survey was designed to assess the participants' knowledge of fermentation, fermented foods, the consumption of fermented foods and awareness of the health benefits. Data were collected from March to June 2021 and analyzed using IBM SPSS 27.0.ResultsCompared with the youngest participants (< 21 years) knowledge of fermentation was higher in older individuals (p < 0.001). More than a half of the participants recognized the role of lactic acid bacteria and yeasts in fermentation process, however, only 18.3% of participants were aware of the role of the molds. Only 25.9% of the participants have become acquainted with fermented foods at home and 62.2% of them were aware of health benefits of fermented foods, but mostly on gastrointestinal health and the immune system.ConclusionsAs people today live predominantly in urban areas and incline towards westernized foods, they often lack the knowledge of fermentation and awareness regarding the nutritional value of fermented foods and their preparation. Steps should be taken to educate younger generations regarding the health benefits of fermented foods especially considering that most of them expressed their interest in learning more about the process.

Prebiotics enhance persistence of fermented-food associated bacteria in in vitro cultivated fecal microbial communities

It is well established that the gastrointestinal (GI) microbiota plays a major role in human health. Dietary interventions, and consumption of fermented foods that contain live microbes, in particular, are among the approaches being investigated to modulate the GI microbiota and improve health. However, the persistence of fermented food-associated bacteria (FAB) within the GI tract is typically limited by host factors that limit colonization and competition with autochthonous microbes. In this research, we examined if the addition of prebiotics, dietary substrates that are selectively metabolized by microbes to improve health, would enhance the persistence of FAB. We evaluated the persistence of bacteria from three live microbe-containing fermented foods—kefir, sausage, and sauerkraut—in fecal microbial communities from four healthy adults. Fecal communities were propagated in vitro and were inoculated with fermented food-associated microbes from kefir, sausage, or sauerkraut at ~107 CFU/mL. Communities were diluted 1:100 every 24 h into fresh gut simulation medium to simulate microbial community turnover in the GI tract. We measured the persistence of Lactobacillaceae from fermented foods by quantitative PCR (qPCR) and the persistence of other FAB through 16S rRNA gene sequencing. FAB were unable to persist in vitro, reaching undetectable levels within 96 h. Addition of prebiotics, including xylooligosaccharides and a mixture of fructooligosaccharides and galactooligosaccharides enhanced the persistence of some species of FAB, but the level of persistence varied by fecal donor, fermented food, and prebiotic tested. Addition of prebiotics also increased the relative abundance of Bifidobacterium species, which most likely originated from the fecal microbiota. Collectively, our results support previous in vivo studies demonstrating the transient nature of FAB in the GI tract and indicate that consumption of prebiotics may enhance their persistence.

Dairy-Based Probiotic-Fermented Functional Foods: An Update on Their Health-Promoting Properties

Numerous studies have shown a link between the consumption of fermented dairy foods and improved health outcomes. Since the early 2000s, especially probiotic-based fermented functional foods, have had a revival in popularity, mostly as a consequence of claims made about their health benefits. Among them, fermented dairy foods have been associated with obesity prevention and in other conditions such as chronic diarrhea, hypersensitivity, irritable bowel syndrome, Helicobacter pylori infection, lactose intolerance, and gastroenteritis which all are intimately linked with an unhealthy way of life. A malfunctioning inflammatory response may affect the intestinal epithelial barrier’s ability to function by interfering with the normal metabolic processes. In this regard, several studies have shown that fermented dairy probiotics products improve human health by stimulating the growth of good bacteria in the gut at the same time increasing the production of metabolic byproducts. The fermented functional food matrix around probiotic bacteria plays an important role in the survival of these strains by buffering and protecting them from intestinal conditions such as low pH, bile acids, and other harsh conditions. On average, cultured dairy products included higher concentrations of lactic acid bacteria, with some products having as much as 109/mL or g. The focus of this review is on fermented dairy foods and associated probiotic products and their mechanisms of action, including their impact on microbiota and regulation of the immune system. First, we discussed whey and whey-based fermented products, as well as the organisms associated with them. Followed by the role of probiotics, fermented-product-mediated modulation of dendritic cells, natural killer cells, neutrophils, cytokines, immunoglobulins, and reinforcement of gut barrier functions through tight junction. In turn, providing the ample evidence that supports their benefits for gastrointestinal health and related disorders.

Association between maternal fermented food consumption and child sleep duration at the age of 3 years: the Japan Environment and Children’s Study

BackgroundUsing cohort data from the Japan Environment and Children’s Study (JECS), we previously reported that the risk of sleep deprivation in 1-year-old children was reduced with a higher maternal intake of fermented foods, particularly miso. The present study, which evaluates children from the same cohort at 3 years of age, is a continuation of that work.MethodsAfter applying exclusion criteria to 104,062 records in the JECS dataset, we evaluated 64,200 mother-child pairs in which the child was 3 years old. We examined the association of the dietary intake of fermented foods during pregnancy with child sleep duration < 10 h at the age of 3 years.ResultsMultivariable logistic regression analysis with the lowest quartile used as a reference revealed adjusted odds ratios (95% confidence intervals) for the second through fourth quartiles of 0.98 (0.90–1.06), 0.93 (0.85–1.01), and 0.85 (0.78–0.94) for cheese intake.ConclusionsThe consumption of fermented foods during pregnancy is associated with reduced risk of sleep deprivation in 3-year-old children, albeit in a limited way.

Persistence of fermented food bacteria in the oral cavity of rats after one week of consumption

Fermented foods constitute a wide source of exogenous lactic acid bacteria (LAB) which could modify the endogenous microbiota of the consumer's digestive tract. This assumption depends on the ability of LAB to persist, at least transiently, in the oral cavity. The aim of this study was to evaluate the persistence of 3 LAB species, Streptococcus thermophilus, Lactococcus lactis, and Lacticaseibacillus paracasei in the oral cavity of rats by feeding them with a daily portion of model cheese containing the three bacteria for one week. Saliva samples were collected 16 h and one week after the last daily cheese intake. Their cheese bacteria contents were quantified by qPCR. When 16 h after cheese consumption, cheese bacteria were detected in the oral cavity of about ⅓ of the rats ranging from 10−3% to 10−1% of the total bacteria. One week after the last cheese intake, 1/8 LAB remains in the oral cavity. This study is a proof of concept showing that LAB can remain in the oral cavity several days after fermented food consumption with variability depending on individuals.

Traditional Fermented Foods and Beverages from around the World and Their Health Benefits.

Traditional fermented foods and beverages play an important role in a range of human diets, and several experimental studies have shown their potential positive effects on human health. Studies from different continents have revealed strong associations between the microorganisms present in certain fermented foods (e.g., agave fructans, kefir, yeats, kombucha, chungkookjang, cheeses and vegetables, among others) and weight maintenance, reductions in the risk of cardiovascular disease, antidiabetic and constipation benefits, improvement of glucose and lipids levels, stimulation of the immunological system, anticarcinogenic effects and, most importantly, reduced mortality. Accordingly, the aim of this review is to corroborate information reported in experimental studies that comprised interventions involving the consumption of traditional fermented foods or beverages and their association with human health. This work focuses on studies that used fermented food from 2014 to the present. In conclusion, traditional fermented foods or beverages could be important in the promotion of human health. Further studies are needed to understand the mechanisms involved in inflammatory, immune, chronic and gastrointestinal diseases and the roles of fermented traditional foods and beverages in terms of preventing or managing those diseases.

Long-term daily high-protein, drained yoghurt consumption alters abundance of selected functional groups of the human gut microbiota and fecal short-chain fatty acid profiles in a cohort of overweight and obese women

• A cohort of overweight and obese women consumed Skyr daily for 4 months. • This study combines longitudinal analysis, quantitative microbiota profiling, and in-depth fecal metabolite analysis. • Skyr consumption successfully transmitted both starter cultures to the gastrointestinal tract. • Intervention-dependent changes in fecal microbiota composition and short chain fatty acid profiles were linked to metabolites of dairy fermentations. • Skyr consumption had major impact on intestinal microbial cross-feeding. The consumption of fermented foods has gained considerable attention due to the ability to deliver live microbes with specific enzymatic activities, and fermentation metabolites, which might play a role in health promotion or disease prevention. The aim of this study was to determine the impact of long-term daily consumption of a high-protein drained yoghurt (Skyr) on intestinal microbial ecology and fermentation activity in a free-living cohort of overweight and obese women (n = 29). Longitudinal analysis and quantitative microbiota profiling identified time intervals with significantly differentially abundant taxa during intervention that differed in functional activity. Our results suggest that ingestion of Skyr persistently modified intestinal microbial cross-feeding activities which altered fecal short chain fatty acid profiles. This study provides a framework indicating the potential of fermented dairy containing starter cultures, lactose and lactate in individualized nutrition or microbiome engineering due to nutritive and microbial components.

Review article: the future of microbiome-based therapeutics.

SummaryBackgroundFrom consumption of fermented foods and probiotics to emerging applications of faecal microbiota transplantation, the health benefit of manipulating the human microbiota has been exploited for millennia. Despite this history, recent technological advances are unlocking the capacity for targeted microbial manipulation as a novel therapeutic.AimThis review summarises the current developments in microbiome‐based medicines and provides insight into the next steps required for therapeutic development.MethodsHere we review current and emerging approaches and assess the capabilities and weaknesses of these technologies to provide safe and effective clinical interventions. Key literature was identified through Pubmed searches with the following key words, ‘microbiome’, ‘microbiome biomarkers’, ‘probiotics’, ‘prebiotics’, ‘synbiotics’, ‘faecal microbiota transplant’, ‘live biotherapeutics’, ‘microbiome mimetics’ and ‘postbiotics’.ResultsImproved understanding of the human microbiome and recent technological advances provide an opportunity to develop a new generation of therapies. These therapies will range from dietary interventions, prebiotic supplementations, single probiotic bacterial strains, human donor‐derived faecal microbiota transplants, rationally selected combinations of bacterial strains as live biotherapeutics, and the beneficial products or effects produced by bacterial strains, termed microbiome mimetics.ConclusionsAlthough methods to identify and refine these therapeutics are continually advancing, the rapid emergence of these new approaches necessitates accepted technological and ethical frameworks for measurement, testing, laboratory practices and clinical translation.

Dietary fiber and fermented food consumption and its link to allergic responses

The authors have no financial conflicts of interest.

Global Regulatory Frameworks for Fermented Foods: A Review.

In recent years, there has been a global resurgence of public interest in fermented foods. In parallel, there have been several new studies that associate the consumption of fermented foods with a variety of beneficial impacts. These combined developments have led to a renewed focus in research and innovation vis-à-vis fermented foods, particularly traditional fermented foods, with an aim to harness this information to develop novel fermented foodstuffs and ingredients and make them available in the market. Consequently, an ever greater and more diverse array of fermented foods, including functional fermented foods with health benefits, are becoming available for public consumption in global markets, with the number expected to grow substantially in the coming decade. This rapidly expanding portfolio of commercially available fermented foods has in turn required an evolution in the corresponding global regulatory frameworks. Due to the innovative and emerging nature of these foods, combined with historical differences in regulator approaches, significant disharmony exists across these frameworks, with individual nations and organizations often adopting unique approaches relating to the establishment of standards and specifications. In this review, we provide an overview of the current regulatory frameworks for a diversity of fermented foods across multiple jurisdictions, with special emphasis on differences in legislative structures and approaches, regulatory harmonization, and current legislative limitations. Overall, the review provides important perspective and context in relation to current global fermented food regulatory practices with possible directions and recommendations for future legislative efforts.

Ethyl carbamate triggers ferroptosis in liver through inhibiting GSH synthesis and suppressing Nrf2 activation

Humans are inevitably exposed to ethyl carbamate (EC) via consumption of fermented food and beverages. EC, known as an environmental toxin, can cause oxidative stress-mediated severe toxicity, but the underlying mechanisms remain unveiled. Ferroptosis is a newly identified ROS-mediated non-apoptotic cell death characterized by iron accumulation and excessive lipid oxidation. In this study, we first found that EC triggered ferroptosis in liver cells by detection of decreased cell viability, GSH, GPX4 and Ferritin levels, as well as increased iron and MDA contents. Ferroptosis inhibitor ferrostatin-1 (Fer-1) pretreatment rescued ferroptotic damage, indicating that ferroptosis was critical for EC-caused cell death. Furthermore, GSH synthesis precursor N-acetylcysteine displayed significant anti-ferroptotic properties and we suggested that GSH depletion might be the main cause of ferroptosis under EC exposure. EC-triggered GSH depletion mainly depended on suppressed GSH synthesis via inhibition of SLC7A11 and GCLC expressions. Notably, EC blocked Nrf2 activation by repression of phosphorylation modification and nuclear translocation, which further resulted in ferroptosis occurrence. We also observed EC-induced liver dysfunction and inflammation, accompanied with oxidative stress, ferroptosis and downregulated Nrf2 signaling in Balb/c mice, which could be effectively reversed by Fer-1 and tBHQ pretreatment. Together, our study indicated that ferroptosis is a new mechanism for EC-caused toxicity, which was attributed to Nrf2 inactivation and GSH depletion.

Effects of an Iranian traditional fermented food consumption on blood glucose, blood pressure, and lipid profile in type 2 diabetes: a randomized controlled clinical trial.

Ash-Kardeh is one of the few fermented foods without a dairy base in Iran, which is traditionally prepared from cereals and plants in the presence of microorganisms (mainly lactic acid bacteria). This study aimed to assess the effects of Ash-Kardeh consumption on blood glucose, lipid profile, and blood pressure in type 2 diabetic patients. Forty-six patients with type 2 diabetes were studied in this randomized controlled clinical trial. Subjects were randomly allocated into intervention (n = 23) and control (n = 23) groups. Individuals of both groups received the usual treatment of diabetic patients, while those in the intervention group, in addition to the usual treatment, received 250g of Ash-Kardeh daily for 6 weeks. Fasting blood glucose, blood pressure, and lipid profiles were measured before and after the intervention. Compared to the control group, Ash-Kardeh consumption led to a significant decrease in fasting blood glucose (P = 0.003), total cholesterol (P = 0.025), triglyceride (P = 0.003), systolic (P < 0.001), and diastolic blood pressure (P = 0.014) in the intervention group. Also, a significant increase in the concentrations of high-density lipoprotein cholesterol (P = 0.048) was observed after Ash-Kardeh consumption. It seems that Ash-Kardeh consumption could improve high blood glucose, lipid profile, and hypertension in type 2 diabetic patients but does not affect low-density lipoprotein cholesterol concentrations. This study was registered on 2019-09-15 in the Iranian Registry of Clinical Trials ( www.irct.ir ) with the code number IRCT20170202032367N3.

SYSTEMATIC REVIEW HUBUNGAN POLA MAKAN DENGAN KEJADIAN HIPERTENSI PADA LANSIA

Introduction: One of the risk factors for hypertension is the wrong dietary habits. The habit of consuming fast food, foods that contain preservatives, sodium and high fat foods are examples of wrong dietary habits. Objective: To conduct a systematic review of the relationship of dietary habits with the incidence of hypertension in the elderly based on a study of the last 5 years. Design: Systematic Review. Sources of comprehensive electronic data searches were conducted on Pubmed, Google Schoolar, Garuda Portal and Mendeley. Review Method: The keywords used in this study are “dietary habit” AND “incidence of hypertenysion” AND “elderly”. The inclusion criteria used in this study are: (1) the population is elderly with hypertension, (2) not research articles with intervention, (3) articles published in 2016-2021, (4) open access free full text, (5) International reputation such as: Scimago and indexed Nationally such as: Garuda and Sinta and (6) articles in Indonesian and English. Results: The number of 9 journals reviewed by researchers showed that most diets cause hypertension in the elderly, such as diets with high sodium intake, intake of fatty foods and consumption of fermented foods or drinks. Conclusion: there is a relationship between dietary habits and the incidence of hypertension in the elderly based on empirical studies of the last five years. Suggestion: the results of this study are expected to be used as information material about a good diet for the elderly so that the incidence of hypertension can be prevented.

Clinical and Preclinical Studies of Fermented Foods and Their Effects on Alzheimer's Disease.

The focus on managing Alzheimer’s disease (AD) is shifting towards prevention through lifestyle modification instead of treatments since the currently available treatment options are only capable of providing symptomatic relief marginally and result in various side effects. Numerous studies have reported that the intake of fermented foods resulted in the successful management of AD. Food fermentation is a biochemical process where the microorganisms metabolize the constituents of raw food materials, giving vastly different organoleptic properties and additional nutritional value, and improved biosafety effects in the final products. The consumption of fermented foods is associated with a wide array of nutraceutical benefits, including anti-oxidative, anti-inflammatory, neuroprotective, anti-apoptotic, anti-cancer, anti-fungal, anti-bacterial, immunomodulatory, and hypocholesterolemic properties. Due to their promising health benefits, fermented food products have a great prospect for commercialization in the food industry. This paper reviews the memory and cognitive enhancement and neuroprotective potential of fermented food products on AD, the recently commercialized fermented food products in the health and food industries, and their limitations. The literature reviewed here demonstrates a growing demand for fermented food products as alternative therapeutic options for the prevention and management of AD.

The efficacy of fermented foods in the treatment and management of diarrhoeal diseases: A systematic review and meta-analysis.

Background: Diarrhoeal disease is a major cause of global infant mortality, and compromises the ability of many countries with respect to achieving sustainable development goals. The WHO's recommendation of Oral Rehydration Solution (ORS) and zinc in the management of this disease, may not be readily available. Consideration and assessment of cultural practices in its management has been an area of increased interest over the last decade. Aim: This study aims to systematically evaluate efficacy of the consumption of traditional fermented foods as functional products for the treatment and management of diarrhoea. Methods: Following PRISMA guidelines, a systematic review was conducted of electronic databases (Cochrane Library, Ovid Medline and Pubmed) databases with no restrictions on language and publication date for RCTs that investigated the effect of consumption of fermented foods on the treatment of diarrhoea in children under five years of age. Results: Seven RCTs were included. Meta-analysis showed that compared to control, consumption of fermented foods significantly reduced mean duration of diarrhoea, -0.61 days; (95% CI, -1.04, -0.18); length of hospitalization, -0.35 days (95% CI, -0.69, -0.02); but not mean daily frequency of stool -2.00 (95% CI,-7.03, 3.04). Conclusion: Limited available evidence suggests that consumption of fermented foods may help reduce duration and severity of symptoms as a treatment of diarrhoea. More high quality research needs to be undertaken to investigate the efficacy of fermented food as an effective alternative to ORS as a potential WHO recommendation for management of diarrhoeal disease.

SARS-CoV-2 Interacts with Mucosal Dysbiosis to Cause the Wide Range of Disease Seen in Covid-19

Hypothesis: SARS-CoV-2 amplifies pre-existing dysbiosis induced mucosal inflammation and this can cause a severe systemic inflammatory disease. The microbial flora perturbation can persist long after the virus has been eliminated leading to a wide range of long Covid symptoms. Evidence: Dysbiosis induced mucosal inflammation increases with age and is strongly associated with the metabolic syndrome (obesity, type 2 diabetes mellitus, ischaemic heart disease, hypertension, and depression). These are risk factors for the conversion of mild to severe Covid-19. Certain common strains of Staphylococcus aureus, which is commonly carried in pharyngeal mucosa, can trigger a cytokine cascade as seen in severe Covid-19. Blood group A and vitamin D deficiency, which are risk factors for hospitalisation in Covid-19 are also associated with increased S. aureus pharyngeal carriage rates. Multi-inflammatory syndrome in children is a post Covid condition which resembles toxic shock syndrome and Kawasaki disease (the former is known to be caused by staphylococcal pyrogenic toxins). A number of studies have shown dysbiosis of the oral mucosa and rectal mucosa in patients who progress to severe Covid-19. The wide range of pathology seen during and following SARS-CoV-2 infection is more in keeping with dysbiosis induced inflammation (multiple pathogenic bacteria at multiple sites) than with an otherwise simple viral induced respiratory tract infection. Implication: Optimization of the microbial flora, prior to encountering the virus, could have reduced the severity of the pandemic. The consumption of fermented foods, especially yoghurt, holds the most promise for reducing dysbiosis induced mucosal inflammation and preventing a wide range of complications. Reduced mucosal inflammation brings not only health but also happiness in which oxytocin has a key role.

New insights of bacterial communities in fermented vegetables from shotgun metagenomics and identification of antibiotic resistance genes and probiotic bacteria

Consumption of fermented foods has grown worldwide due to the purported health benefits. It is thus critical to understand fermented foods microbiome that mainly influences the quality and safety of these foods. This study identified bacterial communities, including functional profiles of probiotics and antimicrobial resistance genes (ARGs), in pickled vegetables commonly consumed in the Middle Eastern, African, and Asian sub-continent regions. Eighteen samples from six pickled vegetables were collected from local markets in Saudi Arabia and analyzed using shotgun metagenomic sequencing. Statistical analyses revealed significant distance and separate clustering of bacterial communities among the different pickle types. Species of Levilactobacillus namurensis, Lentilactobacillus buchneri, Lentilactobacillus parafarraginis, Lactiplantibacillus pentosus, Pectobacterium carotovorum, Leuconostoc carnosum, Weissella confuse were found in a range of dominance in most of the samples. Binning revealed 33 high-quality, metagenome-assembled genomes (MAGs), including 4 MAGs representing putatively novel species of Lactobacillus, Alcanivorax, and Dichelobacter. Moreover, 285 ARGs and variants produce resistance against 20 classes of antibiotics were retrieved, mostly from Enterobacteriaceae contigs. The metagenomes harbored relatively high abundances of carbohydrate fermentation enzymes, as well as metabolic pathways for amino acid metabolism, cofactors and vitamins biosynthesis. Overall, by providing a comprehensive overview of bacterial communities and probiotic bacteria in pickled vegetables, the results suggest the need for more hygienic processing to avoid Enterobacteriaceae contamination and ARG spread.

Who Benefits from Fermented Food Consumption? A Comparative Analysis between Psychiatrically Ill and Psychiatrically Healthy Medical Students.

Probiotic therapies and fermented food diets hold promise for improving mental health. Although in this regard psychiatric patients appear to benefit more than healthy individuals, no research has been performed to directly evaluate this hypothesis. The present study examined a cohort of medical students facing a stressful event, and some of the students reported suffering from chronic psychiatric diseases. The amount of fermented food consumption was calculated with the use of seven-day dietary records, while depressive and anxiety symptoms were assessed with the use of the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7, respectively. In psychiatrically healthy medical students under psychological stress (n = 372), higher fermented food consumption was associated with more depressive and anxiety symptoms. In contrast, psychiatrically ill medical students (n = 25, 6.3% of all the participants) were found to present a negative association between the amount of fermented food consumed and the severity of depressive symptoms (adjusted β −0.52, 95% CI −0.85 to −0.19, p = 0.0042); however, this relationship was insignificant for anxiety symptoms (adjusted β −0.22, 95% CI −0.59 to 0.15, p = 0.22). A significant interaction was found between the consumption of fermented food and psychiatric diagnosis in predicting depressive symptoms (p = 0.0001), and a borderline significant interaction for anxiety symptoms (p = 0.053). In conclusion, psychiatrically ill people, but not healthy ones, may benefit from fermented food consumption in terms of alleviation of depressive symptoms. Our findings require cautious interpretation and further investigation.