Smell Training is olfactory therapy
What is smell training? It is a therapy for people who have suffered smell loss.
Some people lose their sense of smell after a virus or long-term sinus problems. Others lose it after a traumatic brain injury. You can be born without a sense of smell, and it can also be an indicator of other health conditions. Some anosmia has no known origin and is referred to as idiopathic.
Is it for me?
Smell training is for people who have had some natural recovery already, and can experience some smell messages, even if what they smell doesn't make sense. This website is for people who have some, even if very reduced, olfactory function. Smell training is not a cure, but a way of amplifying your recovery. Think of it as physiotherapy for your nose.
Treatments - seeking a doctor’s advice
Anyone with a smell disorder should speak with their doctor, as causes vary and can have an important impact on health. Anosmia is not always widely understood by GPs and this can be frustrating for patients.
The best approach is to be informed about smell loss before your GP visit. This patient information booklet from the University of Dresden is a great resource.
The “Hummel 4” method of smell training
This method, proposed by Professor Thomas Hummel of Dresden University, involves smelling four essential oils twice a day for a few minutes. This is the original smell training method.
The recommended oils are rose, eucalyptus, lemon and clove. You may not notice any smell in the beginning. The important thing is to concentrate on what you might smell. Your twice daily smell training should take just a few minutes. Be sure to pause in between odours to allow your nose a chance to rest in between.
For post-viral patients, there can be a period of time when smells are distorted (known as parosmia) and anything you might smell might also be unlike what you are expecting to smell. This is quite normal, although very frustrating. The best advice for parosmia is to continue to smell train. The stimulation of your sense of smell is therapeutic and hastens the recovery process.
You need to smell train for at least several months, and you need to do it daily. It helps to keep your smell training equipment somewhere handy where you will remember to use it frequently – for instance by your desk, in the bathroom, or in the kitchen. For full details, look here.
Will smell training work for me?
Smell training has been shown in clinical trials to be most useful for patients with post-viral olfactory loss. There is however mounting evidence to show that it may be of use to some of those patients who have had traumatic brain injuries (TBI). Whether or not a TBI patient will respond depends on how bad their original injury was.
While it is better to start smell training as soon as possible after losing your sense of smell, it can also benefit those who have had anosmia for some time.
For post-viral patients, even those who really feel they have no sense of smell at all, smell training can be helpful.
How does smell training work?
Smell training stimulates the olfactory complex in the brain. Nancy Rawson, Associate Director of the Monell Center in Philadelphia and cell biologist gives her comments on what is happening when patients smell train here. In clinical trials, the patients who used smell training fared better in the areas of identification and discrimination of smells than patients who did no training at all.
Also, patients who trained with higher concentrations of smells did better than those who trained with “less smelly” samples. Even after stopping the smell training, the patients who had used the method more or less maintained their improvement. There is a list of scientific papers relevant to smell training research here.
Keeping a record of your smell training
It is worthwhile to make notes about when you smell train and what you are noticing.
You needn’t make notes every day. Once a week or every two weeks is plenty. This will help you notice any changes taking place.
Be patient. The nerves that serve the olfactory system do regenerate, but they regenerate very slowly.
Are you interested in a guided smell training course? Check out what's on offer here.