Anosmia is the complete loss of smell. Loss of smell is extremely dangerous as it diminishes one’s ability to detect toxins such as a gas leak, smoke, or rotten food. In addition, loss of smell commonly leads to loss of interest in eating which in turn leads to weight loss, malnutrition, or depression. The ability of one’s smell correlates with one’s ability to taste, so loss of smell will cause taste buds to be inadequate. One’s sense of smell is at its peak between the ages of 30 and 60. After age 60, sense of smell begins to steadily decline. The sense of smell derives from the first cranial nerves also known as the olfactory nerves. There are between 6 million and 10 million olfactory receptor cells located on the olfactory membrane. The olfactory nerves are located on the base of the brain’s frontal lobes posterior to the eyes and superior to the nose (the top part of the nasal cavity between the eyes). A molecule is released from a specific substance, such as coffee, which stimulates the olfactory cells. These olfactory cells will transmit the information to the brain’s olfactory bulb and the smell is then identified and distinguished. There are numerous things that can potentially disrupt this process and cause either temporary loss of smell or permanent loss of smell. If there is damage to the olfactory nerves, loss of smell is more likely to be permanent.
If there is nasal congestion due to a cold, the molecules containing the specific smell will not reach the olfactory nerves and as a result smell will not be identified. In this case, the olfactory nerves will not have any information to transmit to the brain’s olfactory bulb. Other causes of Anosmia include nasal polyps on the nasal membrane and smoking cigarettes. In permanent cases of Anosmia, causes include exposure to toxic chemicals, use of cocaine, certain medications, infections, head injuries or viral infections that destroy the olfactory nerves, age, Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, or undergoing treatments that involve radiation. The Penn study demonstrates that the more cigarettes a person has smoked, the greater the loss of the sense of smell, and the longer it takes for one to regain his or her sense of smell after he or she quits smoking. In certain circumstances, Anosmia is not treatable. These circumstances involving permanent Anosmia include suffering from olfactory nerve damage or obtaining Anosmia simply from age. Although these circumstances are not treatable, there are numerous ways to maintain a healthy lifestyle with the loss of smell. For example, smoke alarms and carbon monoxide detectors should be placed in one’s home and workplace.