Purpose of Review <p>Olfactory function is certainly associated with cognitive health, and the severity of loss of smell (LoS) has been associated with the rate of cognitive decline. In this review, we describe the relationship between olfactory dysfunction and cognitive decline, focusing on its relevance in type 2 and non-type 2 inflammatory upper respiratory diseases. We also highlight the relevant correlation between the alteration of the components of olfaction, such as odor identification, and the progression in cognitive decline leading to dementia.</p> Recent Findings <p>A relevant number of studies suggest that olfactory identification impairment may predict the progression of cognitive decline from normal aging to mild cognitive impairment and dementia.</p> Summary <p>In this review, we describe the association between olfactory dysfunction and cognitive decline, focusing in its relevance in type 2 and non-type 2 inflammatory upper respiratory diseases.</p>