The sense of taste is one of the five vital senses every human being has. These senses are vital for the successful survival of a person since it involves the food we eat. The taste of a food is often an indication of edible or inedible food for the early man who was still evolving. For example, a bitter or sour taste was an indication of poisonous inedible plants or of rotting protein-rich food, while the tastes sweet and salty, on the other hand, were often a sign of food rich in nutrients.
What is generally categorized as “taste” is basically a bundle of different sensations: it is not only the qualities of taste perceived by the tongue, but also the smell, texture and temperature of a meal that are important. The “coloring” of a taste happens through the nose. Only after taste is combined with smell is a food’s flavor produced. If the sense of smell is impaired, by a stuffy nose for instance, perception of taste is usually dulled as well.
Like taste, our sense of smell is also closely linked to our emotions. This is because both senses are connected to the involuntary nervous system. That is why a bad taste or odor can bring about vomiting or nausea. And flavors that are appetizing increase the production of saliva and gastric juices, making them truly mouthwatering. There are five basic taste flavors which all food is basically categorized as when it is tasted. These are sweet, sour, bitter, salty and savory.
Life without a sense of taste is pretty difficult and there is a reduction in quality of life for people who have a reduced or absent sense of smell. At no time was this fact better appreciated than the turn of 2020 which heralded a new normal life caused by the world wide pandemic – the COVID 19 and its symptoms, of which loss of sense of taste was a common one. A study reported that 43% of people with COVID-19 who had loss of sense of smell and taste reported feeling depressed and 56% reported decreased enjoyment of life in general while experiencing loss of smell or taste. The most common quality-of-life concern was reduced enjoyment of food, with 87% of respondents indicating it was an issue. Loss of appetite and unintentional weight loss continue to pose challenges for such patients.
What is the COVID-19 and its symptoms?
The COVID-19 is caused by the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which was first identified in Wuhan, China, following reports of serious pneumonia. Till date, (Feb 2022) the virus has infected over 435 million people and killed over 5.9million people worldwide. COVID-19 transmits when people breathe in air contaminated by droplets and small airborne particles. The risk of breathing these in is highest when people are in close proximity, but they can be inhaled over longer distances, particularly indoors.
The symptoms of COVID-19 include: Fever or chills, Cough, Shortness of breath or difficulty breathing, Fatigue, Muscle or body aches, Headache, Sore throat, Congestion or runny nose, Nausea or vomiting, diarrhea, and loss of taste or smell.
COVID-19 can also cause complications like: Acute Cardiac Injury, Acute Kidney Injury, Pneumonia, Acute respiratory failure, Septic Shock, Blood Clots, and death.
How does COVID-19 cause loss of taste?
Loss of taste often occurs with loss of smell and can be confused with each other sometimes. However, loss of taste is an established symptom of COVID-19. A study among COVID- 19 patients reported that over a third (37%) of people who suffered from the disease reported a loss in sense of taste. This was also higher for women, and those between the ages of 18 to 50 years.
There has been several theories of how COVID-19 causes loss of taste in individuals. One explanation of could be that taste nerves are damaged following central nervous infection by SARS-CoV-2. However, the low rate of serious central nervous system infections in COVID-19 infected people with loss of smell makes this explanation unlikely. Another, more likely explanation is that the inflammation caused by the disease releases some substances called inflammatory cytokines which spreads to the taste buds and causes them not to be renewed. In order to function properly, the taste buds need to be continually renewed, so this impairment in its renewal may led to a reduced sense of taste in individuals with the disease. The cytokines have also been proposed make the taste buds cells develop the receptors for the virus to bind to them and make it easy for them to be directly infected with the virus. This can also lead to their reduced function causing loss of smell.
How to get sense of taste back after COVID?
The good news about loss of taste and smell after COVID -19 is that it is mostly reversible. For about a quarter of people with COVID-19 who have one or both of these symptoms, the problem resolves in a couple of weeks. But for most, these symptoms persist. Though not life-threatening, prolonged distortion of these senses can be devastating and can lead to lack of appetite, anxiety and depression. Some studies suggest that there’s a 60% to 80% chance that these people will see improvement in their sense of smell within a year.
If you have COVID or just recovered and are having issues with tasting food, the NHS recommends the following helpful tips while you wait to fully recover.
- Choose foods that appeal to you to ensure you eat well, but continue to retry foods as your taste preferences may change.
- Keep your mouth clean and healthy by brushing your teeth morning and evening and rinsing your mouth with water if it feels dry or uncomfortable. Avoid alcohol based mouthwashes.
- Try experimenting with different flavors, textures and temperatures of food to see which you find more edible. You may find bland flavors such as plain chicken, fish, tofu and rice may be easier to eat especially if you are still feeling nauseated or have an unsettled stomach. Cold or room temperature foods may also be more acceptable.
- Because high protein foods can take on a bitter or metallic taste. Try marinating meats with sweet/sour marinades to change the flavor and try a variety of protein sources to find the most enjoyable one for you; red meat, poultry, fish, egg, cheese, vegetarian meat alternatives, beans and pulses.
- Adding strong flavors to food can help with taste e.g. herbs and sauces such as apple sauce, mint sauce, cranberry sauce, horseradish, mustard and pickles. Spices can also improve flavor.
- Sharp/tart flavored foods and drinks such orange, lemon, lime flavors can be useful in balancing very sweet tastes. Sucking boiled sweets and mints may also help refresh your mouth before and after eating.
- If foods have a metallic taste, try plastic cutlery instead of metal and use glass cookware.
- Salty or bitter taste changes may be improved by choosing low salt varieties and adding sweet flavors to food or drink, such as sweetener, honey, or sugar.