Nutrition is not a one-size-fits-all endeavor. Calorie and nutrient needs vary throughout the life cycle, and rise and fall based on age, sex, activity level, and illness or disease—not to mention formative periods like pregnancy or infancy through adolescence. Key nutrients such as omega-3 fatty acids, iron, collagen and more can all contribute to various aspects of health, whether supporting cognition, immunity, bone and muscle development, or a host of other activities across the lifespan.