Smell occurs when nerve receptors in your nose send messages to your brain. The sense of smell plays an important role in perception of foods. The interaction of the oral and nasal senses blend together to give us the impression of a certain food, or increase the sensory perceptions we receive. Smells can also create emotional responses to food. This is because emotions and smell sensations overlap in your brain.
Smells can create both positive and negative emotional responses to food.
A positive response can improve the desire to eat, while a negative response may decrease the desire to eat. Declining taste and smell is a normal part of the aging process for many people. Age-related impairment of the senses can be caused by many factors including environmental pollutants. As a result, taste buds and smell receptors do not function as well as in earlier years, causing a decline in the senses of taste and smell. These changes can decrease the desire for food.