Fermented foods refer to beverages or foods made by carefully regulated microbial growth and the enzymatic conversion of dietary components. Fermented foods have recently become more popular. Studies on fermented foods suggest the types of bacteria and bioactive peptides involved in this process, revealing linkages that may have impacts on human health. By identifying the bacteria and bioactive peptides involved in this process, studies on fermented foods suggest relationships that may have impressions on human health. Fermented foods have been associated with obesity, cardiovascular disease, and type 2 diabetes. In this article, fermented dairy products, vegetables and fruits, legumes, meats, and grains are included. Two elements in particular are emphasized when discussing the fermentation of all of these foods: bioactive chemicals generated during fermentation and microorganisms involved during fermentation. Organic acids, bioactive peptides, conjugated linoleic acid, biogenic amines, isoflavones, phytoestrogens, and nattokinase are a few of the bioactive compounds included in this review. Also, certain bacteria such as Lactobacillus, Bifidobacterium, Streptococcus, and Bacillus species, which are utilized in the fermentation process are mentioned. The effects of both substances including anti-fungal and antioxidant properties; the modulation of intestinal microbiota; anti-inflammatory, antidiabetes, anti-obesity, anticancer, and antihypertension properties; and the protection of cognitive function are explained in this review.

Background: Human breast milk is a complex biological fluid containing multifaceted biological compounds that boost immune and metabolic system development that support the short- and long-term health of newborns. Recent literature suggests that human breast milk is a substantial source of nutrients, bioactive molecules, and exosomes. Objectives: This review examines the factors influencing exosomes noted in human milk and the impacts of exosomes on infant health. Furthermore, it discusses potential future prospects for exosome research in dietetics. Methods: Through a narrative review of the existing literature, we focused on exosomes in breast milk, exosome components and their potential impact on exosome health. Results: Exosomes are single-membrane extracellular vesicles of endosomal origin, with an approximate radius of 20–200 nm. They are natural messengers that cells secrete to transport a wide range of diverse cargoes, including deoxyribonucleic acid, ribonucleic acid, proteins, and lipids between various cells. Some studies have reported that the components noted in exosomes in human breast milk could be transferred to the infant and cause epigenetic changes. Thus, it can affect gene expression and cellular event regulation in several tissues. Conclusions: In this manner, exosomes are associated with several pathways, including the immune system, oxidative stress, and cell cycle, and they can affect the short- and long-term health of infants. However, there is still much to learn about the functions, effectiveness, and certain impacts on the health of human breast milk exosomes.

Alzheimer's disease (AD) is the most common form of dementia in the elderly and is a chronic neurodegenerative disease that is becoming widespread. For this reason, in recent years factors affecting the development, progression and cognitive function of the AD have been emphasized. Nutrients and other bioactive nutrients are among the factors that are effective in AD. In particular, vitamins A, C and E, vitamins B₁, B₆ and B₁₂, folate, magnesium, choline, inositol, anthocyanins, isoflavones etc. nutrients and bioactive nutrients are known to be effective in the development of AD. Nutrients and nutrient components may also have an epigenetic effect on AD. At the same time, nutrients and bioactive food components slow down the progression of the disease. For this reason, the effect of nutrients and food components on AD was examined in this review.

Type 2 diabetes mellitus (T2DM) is a multifactorial metabolic disorder described by chronic hyperglycemia, insulin resistance, as well as low-grade inflammation. Recent research highlights the vital role of the gut microbiota in the pathogenesis and progression of T2DM. Dysbiosis can impair intestinal barrier integrity, promote systemic inflammation, and contribute to insulin resistance and glucose metabolism dysfunction. This review article investigates the mechanisms by which probiotics interact with gut microbiota and host signaling pathways to impact the onset and complications of T2DM. Databases were searched, and related articles were added, to get a thorough overview of the relationship between probiotics and T2DM and its complications. Probiotics have appeared as potential modulators of the gut microbiome, capable of restoring microbial balance and strengthening intestinal barrier function. Probiotics can influence glucose homeostasis through their multifaceted effects on the gut microbiota and host metabolism. Through the production of beneficial metabolites, suppress α-glucosidase activity, enhance short-chain fatty acid (SCFA) levels, competitive inhibition of pathogenic bacteria, regulation of gut-derived neurotransmitters such as serotonin, improve intestinal, and immune functions, probiotics may alleviate key mechanisms involved in T2DM development and its complications.

Multiple Sclerosis (MS) is a chronic disease with autoimmune and neurodegenerative features that affect the nervous system. Genetic predisposition and environmental factors, such as vitamin D deficiency and dysbiosis activating a pro-inflammatory response, have a role in the etiology of the disease. In this context, the interactions of vitamin D with the gut microbiota and immune system have attracted attention in recent years. Vitamin D (1,25-dihydroxycholecalciferol) modulates the immune response by binding to the Vitamin D receptor (VDR). This pathway supports the functions of regulatory T cells by suppressing the activity of T helper cells 1 and 17 (Th1 and Th17). In MS patients, dysbiosis is characterized by a decrease in microbial diversity, and an increase in pro-inflammatory species is observed when compared to healthy individuals. Vitamin D has protective effects on eubiosis via VDR in intestinal epithelial cells, also reducing intestinal permeability by regulating tight junction proteins. In this way, vitamin D may contribute to the prevention of systemic inflammation. Although the relationship between vitamin D and the immune system is well documented, studies that address the triad of vitamin D level, gut microbiota, and immune response in MS are still limited.