Less common causes of smell and/or taste loss or disorders can include:
- Age related degeneration or dementia:
Many people experience some loss of sense of smell as they get older. Just as our ability to hear and see declines, so does our sense of smell and taste – we also lose our ability to discriminate between smells as we age. It has been reported that more than 75% of people over the age of 80 years have evidence of major olfactory impairment and that olfaction declines considerably when we reach this milestone. It is widely accepted that taste disorders are far less prevalent than olfactory loss.
- Treatments for cancer:
Some cancer treatments can cause changes to taste sometimes making food taste different, “off” or metallic. These can include:
- Chemotherapy drugs.
- Targeted cancer drugs.
- Other prescribed drugs to combat side effects such as anti-sickness medication.
- Radiotherapy to the mouth may have a permanent effect on the sense of taste which may improve slowly.
- Radiotherapy for some types of head and neck cancer can also affect the salivary glands which can cause changes to the sense of taste.
You might also find that you go off certain foods because they taste different. Further support and advice about coping with changes to taste caused by cancer treatments can be found at Cancer Research UK.
- Some neurodegenerative conditions such as Parkinson’s disease:
This may be due to degeneration of the anterior olfactory nucleus and olfactory bulb, one of the first parts of the brain affected by Parkinson’s. This can happen so gradually that you’re not even aware of it.
Losing your sense of smell and taste can make you lose interest in food. Diseases of the nervous system such as Parkinson’s (and Alzheimer’s) may appear after the onset of a loss of the sense of smell. It is thought that anosmia may precede the other signs of these diseases by some 5 or more years. At first glance, these patients may therefore not appear to have any other problems other than anosmia and may arise from a group of sufferers where no cause is identified (idiopathic).
- Things to help manage changes to smell and taste caused by other conditions:
There are a range of medical causes which can lead to problems with the sense of smell or taste including liver failure, underactive thyroid gland and diabetes. These can be screened for with blood tests. Epilepsy and toxic rhinitis also have associations with olfactory disturbances as do a number of medications take for other conditions.
If you are experiencing changes to your smell and taste as a result of another health condition as described above in this section or above, you might find the following tips are helpful to maintain a healthy diet.
- Eat four or five small meals during the day instead of three large meals.
- Eat cold food, including yoghurt, ice cream or jelly desserts. Cold food may taste better than hot food.
- Eat fresh, uncooked vegetables. Cooked vegetables can have strong odours that may not be appealing.
- Drink lots of fluids – find one that you enjoy or are able to best tolerate.
- Test new foods to find ones you like.
- Use plastic forks and spoons if food tastes metallic.
- If food tastes bland, marinate foods to improve their flavour or add spices to foods.
- If red meat tastes strange, switch to other high-protein foods such as chicken, eggs, fish, peanut butter, turkey, beans, or dairy products.
- If foods taste salty, bitter, or acidic, try sweetening them.
- If you have a bad taste in your mouth, try sugar-free lemon drops, chewing gum or mints.
- Idiopathic loss – this means the cause is unknown:
This refers to patients in whom after extensive testing no cause for the loss of sense of smell is found. It is important that this diagnosis is made only after blood tests and brain scans have been performed. Patients in this category may go on to develop Parkinsons Disease or Alzheimer’s.
Other causes of smell and taste disorders:
- Exposure to dangerous chemicals such as pesticides or solvents
- Abuse of drugs inhaled through the nose
- Pollution and poor air quality