Cancer and its treatment like radiotherapy, chemotherapy negatively impact taste and smell.
Cancers are different types.
Some types of cancers involve the peripheric end organs or interfere with neurologic pathways of smell and taste.
However, it is quite difficult to comprehend sensory perception distortion with cancer progression and the application of cancer therapies.
Medical researchers explained that chemotherapy and radiation therapy may alter taste and smell by damaging olfactory receptor cells, taste receptor cells, modifying cell surface and receptors along with disturbing neural coding.
Dysgeusia (condition of altering taste sensation) and ageusia (complete loss of taste) are two very common complaints of cancer patients after receiving chemotherapy and radiation therapy.
Both of these treatment processes may damage the sensory receptors that lead to dysgeusia or even ageusia.
Patients who receive chemotherapy and radiation therapy to treat their head and neck cancer often have olfactory dysfunction and cause altered or complete loss of smell.
Every cancer treatment differently alters senses.
For example, chemotherapy which slows down the cancer growth can damage the taste-buds cells.
Nerve endings also get affected with chemotherapy that can alter the senses of hot and cold foods in the mouth.
Radiation therapy applied to treat head and neck cancer not only damages the taste buds but also affects the salivary gland.
Thus, taste, smell, and feel for food deviate from the normal.
Surgical interventions in the mouth and nose area may affect the part of the tongue, nose, or salivary glands, changing the way you taste, smell, or feel food.
Metabolic changes due to the occurrence of cancer can cause altered taste.
Some cancer-related deficiencies of vitamin A, niacin, and zinc can cause dysgeusia.
But changing of taste cannot always occur due to cancer, as fungal infections like oral ulcers, thrush, and xerostomia (dry mouth) can also lead to dysgeusia.
Xerostomia associated with cancer treatment mainly occurs due to treatment-induced salivary gland damage and makes the mouth dry.
One of the key functions of saliva is to help taste buds in flavor recognition.
Prolonged dry mouth can cause tooth decay and that also affects oral health.
Therefore, cancer patients may require checking up on their mouth health and teeth after a regular interval.
Mucositis is another oral health concern in cancer.
Cancer treatment can cause damage to the cell lining of the mouth and gut.
Therefore, a mouth ulcer is a commonly associated problem and causes increased sensitivity to hot, cold, salty, spicy, or acidic foods and drinks.
Cancer or its treatment-related changes of taste include metallic taste, excessive salty or bitter taste, and detestation of certain foods can even cause nausea and vomiting symptoms.
All these unpleasant side effects of cancer and cancer treatment cause a noticeable fall in the nutritional status.
Loss of the eating desire due to inability to taste and smell of the foods decreases appetite and causes anorexia, severe weight loss, muscle wasting.
The above-mentioned sensory problems like dysgeusia or ageusia have no specific treatment.
But it is always suggested that talk to the healthcare team. They can give some useful recommendations to alleviate some of the discomfort and lack of enjoyment while eating.
Instead of taking hot foods eat cold foods to reduce the metallic taste in the mouth.
Cold meats may also be easier to tolerate.
Eat more bland foods if the patient has a complaint of excessively salty food.
Take a smaller portion of the meal at a time to feel a better taste in the mouth, but it requires frequent intake.
In case of complete loss of taste, then eat highly seasoned foods which should be at room temperature (neither very hot nor very cold).
Almost 77% of cancer patients have a complaint of taste dysfunction. Cancer patients less frequently experienced fading of smell sensitivity.
It is expected that dysfunction of taste and smell may responsible for anorexia.
But adequate nutritional diet provides energy to cancer patients to withstand cancer and treatment-related complications.
Therefore, detailed clinical studies require for checking the appetite loss of cancer patients often common in cancer patients.