Abstract
The immune system is a complex, intricate organ system with features like flexibility, recognition, discriminating potential between self from non-self, and memory to defeat notorious external and internal threats to human health functioning. Innate immunity is inborn, and acquired immunity develops through secondary education; they are interconnected, interdependent, and execute tasks with bidirectional communications. A deeper understanding of immune biology revealed a remarkable contribution of the immune system in several chronic illnesses, and has taken a central stage in pathophysiology. In essence, the weakened or overactivated immune system leads to these chronic illnesses. Modulation of the immune system is an efficient and valid approach to prevent the underlying pathophysiology of such diseases. A gamut of natural immunomodulators targeted at specific or non-specif immune cells has delineated their potential to achieve the equilibrated and balanced immune system. Preclinical and clinical studies demonstrated the implication of microbiota, nutrients, natural herbs, and micronutrients for immunostasis. The immune system's complexity, its close association with the endocrine and nervous system, target identification, and convenient, reliable tools to assess immune function and modulation are a few limitations that hampered the attainment of immunostasis. Despite these limitations, novel therapies targeted at immunomodulation in chronic diseases are promising and paving the future path to novel therapeutics.