What can cause loss of smell and taste are numerous factors, such as COVID-19, nasal blockage, deviated septum and more.
Loss of the sense of smell is termed anosmia, and loss of the sense of taste is termed ageusia. The olfactory area in the nose controls both smell and taste, so any inflammation or infection to the nose and sinus areas causes anosmia and ageusia.
Whenever there is a loss of smell, loss of taste also follows. Your taste buds detect a food's sweetness, sourness, bitterness or saltiness. The specifics, such as whether that sweet taste is from a grape or an apple, are determined by your nose.
Loss of smell and taste can be caused by various factors including:
- Illness or infections, such as viral sinus infections, COVID-19, cold or flu and allergies
- Nasal blockage (the passage of air decreases affecting smell and taste)
- Polyps in the nose
- Deviated septum
- Injury to the head (the nerves that carry impulses may be damaged)
- Injury to the nerves of the nose such as the olfactory nerve
- Dental or oral problems
- Dry mouth
- Damage to the salivary gland (taste cannot be appreciated in the absence of saliva)
- Changes in hormones (pregnancy)
- Vitamin D deficiency or malnutrition
- Intake of certain medicines (antidepressants, antibiotics and heart medications)
- Exposure to chemicals such as solvents and insecticides
- Radiation therapy for head and neck cancer
- Snorting of drugs through the nose
- Smoking cigarettes
- Alcohol intake
- Aging (especially in people older than 60 years)
- Genetics (few people may be born with these disorders)
Other rare conditions that cause a loss of smell and taste include:
- Hormonal disorders
- Central nervous system disorders
- Tumors of the brain
- Psychiatric conditions
- Alzheimer’s disease
- Tumors of sinus cavities or nose
- Autoimmune disorders
- Turner syndrome
Some illnesses or risk factors can cause loss of scent that is reversible, partially reversible or permanent. Examples are as follows:
- When a person quits smoking or uses drugs, their sense of smell normally improves although the amount of improvement varies.
- Loss of smell caused as a side effect of medicines may be temporary or permanent.
- Breathing chemicals may cause permanent loss of smell.
What health issues are associated with loss of smell and taste?
Anosmia and ageusia may be signs of an underlying disease, which can affect your quality of life. Problems with taste and smell might indicate various health issues, such as:
- Kidney disease
- Poor nutrition
- High blood pressure
- Nervous system disease
- Multiple sclerosis
- Parkinson’s disease
- Alzheimer’s disease
What is the importance of smell and taste?
Sense of smell and taste greatly improve one’s quality of life. Here are some factors that explain the importance of smell and taste:
- The fragrance of food stimulates appetite, and a loss of smell can result in a loss of appetite and interest in food.
- Saliva production can be reduced if you lose your sense of smell, making dry foods, such as biscuits and crackers, more difficult to eat as a result of this.
- Changes in taste may cause you to avoid certain items, such as meat, resulting in a nutrition deficiency and potentially misleading you into adding more spice and salt to food that may later cause medical issues, such as gastric irritation and high blood pressure.
- Consumption of rotten/spoiled food is harmful to the body, and your sense of smell and taste helps you identify and avoid spoiled food and contaminated water.
- In the absence of smell and taste, your satiety reduces, which makes you eat more leading to health issues and weight gain.
- Sense of smell and taste help form new memories and recall old ones, causing a powerful emotional response.
- Smell and taste also act as warning signs and alert us about harmful events such as a gas leak, toxic chemical fumes or fire.
- When you lose your sense of smell, you may not realize when you need to take a bath, apply deodorant or wash your clothes, which may result in a lack of hygiene.
- With damage to the areas that deal with smell and taste, other nearby sections of the brain may also be affected, leading to several problems, including:
- Emotional problems such as depression and irritability
- Behavioral problems such as aggressiveness and impulsiveness
- Inability to understand and respond well to other’s feelings and needs
If you observe any changes in your sense of smell and taste, you must consult an otolaryngologist who specializes in the diagnosis and treatment of conditions related to the ear, nose and throat, along with the mouth and parts of the neck and face. They examine and perform special tests to identify the cause of the condition and provide treatment accordingly.