The Underexplored Dimensions of Nutritional Hormesis.

PURPOSE OF REVIEW: Hormesis is biphasic response wherein low and high doses of chemical and nutrient confer beneficial and toxic effects respectively, typically in a U-shaped manner. Hormesis is intricately related to bioenergetic state of a cell, and therefore, nutrition impacts it. Excessive nutrition can halt the endogenous antioxidant synthesis leading to cytotoxic effects. While low and optimum doses of the same bring about hormetic stimulation that can exalt the antioxidant response and reduce susceptibility towards degenerative diseases. The sirtuin family of proteins is triggered by mild stress of calorie restriction and exerts hormesis. Similarly, several phytochemicals and micronutrients are known to bring about health benefits at optimum dose and deleterious effects at high doses. Despite this attribute, nutritional hormesis is not very well researched upon because the magnitude of hormetic effect observed is generally quite modest. There is no precise regulation of optimal intake of certain foods to witness hormesis and no characterization of any biomarker that reports stress responses at various doses above or below optimal intakes. There is a major gap in research between nutrition and hormesis being affected by sirtuin family of proteins, phytochemicals, and micronutrients. RECENT
FINDINGS: Mild stress of calorie restriction elevates sirtuin protein and effect of sirtuin protein on hormesis has been recently reported. More foods that enhance sirtuin protein, phytochemicals, and micronutrients need to be explored in relation to hormesis and associated health benefits.