Throughout history, ethnic fermented foods have played a significant role in traditional diets by providing distinct flavors and a host of health advantages. This chapter explores these traditional foods’ nutritional value and health benefits, emphasizing their place in contemporary nutrition. Fermentation introduces healthy bacteria that support gut health and improve the bioavailability of nutrients, such as vitamins, minerals, and vital amino acids. Fermented foods from ethnic cultures, such as tempeh, kimchi, and idli, are full of bioactive substances with anti-inflammatory, antioxidant, and immunomodulatory qualities. These meals help with better immune system performance, better digestion, and a lower chance of developing chronic illnesses like diabetes and cardiovascular disease. There is no denying the benefits of ethnic fermented cuisine from throughout India in terms of immunity and general well-being. There are many different ethnic fermented dishes that may be based on meat, grains, legumes, or vegetables. This chapter also looks at the methods utilized to evaluate the nutritional value of fermented foods, emphasizing how crucial it is to maintain traditional fermentation methods in the face of urbanization and shifting dietary preferences. This chapter seeks to thoroughly understand the nutritional and physiological advantages of ethnic fermented foods that are explored by combining modern study with traditional knowledge. It then makes the case for including these foods in modern diets to improve health outcomes. We have not yet fully examined their potential health advantages and immune-boosting capabilities. Additionally, frequently downplayed, and unstudied is the significance that bacteria play in these fermented meals.