Train your sense of smell

Improve your sense of smell through odor training? It may sound strange, but it certainly makes sense. Training muscles by going to the gym or practicing a musical instrument every day ensures that you (hopefully) progress in what you practice. So you must also see the training of the sense of smell. It is, as it were, physiotherapy for the nose. That training your sense of smell is actually useful is evident from various studies and studies. However, it does not make sense in every condition of the sense of smell. On this page we will provide more background information about odor training.

Research on smell training

In 2009, Professor Thomas Hummel of the University of Dresden started an investigation to see whether daily, intensive smelling of different odors has a positive effect on the sense of smell. The study lasted 12 weeks and was carried out under a group of people with anosmia. These people had all lost their sense of smell due to head injuries, severe infection of the upper respiratory tract, or other unaccountable reasons. One group had to smell daily four different scents (rose, eucalyptus, lemon and cloves) in the morning and evening over a period of 12 weeks. The other group did not participate in the odor training. Both groups were tested for odor at the beginning and end of the study using the Sniffin ‘Sticks fragrance pens. This showed that a large percentage of the group of people who had followed the odor training had a better score on the odor tests at the end of the study compared to the group that had not followed odor training.

In addition to Dr. Hummel there are also several other studies on the effect of odor training showing that the 2 times daily smell smell has a positive effect on the development of the odor ability. The effect is particularly noticeable in daily training of the sense of smell for 6-7 months. The effect of the odor training, however, is highly dependent on each condition. It is certainly not a medicine but a way to speed up and stimulate the recovery.

Odor training with the Hummel method

The most commonly used odor training is based on the research of Professor Thomas Hummel from the University of Dresden. This training consists of 2 times a day intensive smelling of 4 different scents: rose, eucalyptus, lemon (lime) and clove. This is the original fragrance training as prescribed by (ENT) doctors worldwide. This training can be performed with the help of 4 fragrance pens or with 4 oils.

These pens are in collaboration with Dr. Hummel developed by the company Burghart and available through our webshop. The advantage of these pens is that they last for a long time (about 1-1.5 years) and are easy to use. They are, as it were, four felt-tip pens that are not provided with ink but with natural fragrances. Each pen has a best-before date so you can be sure that the pens have the correct fragrance strength and are reliable for the training. As an alternative to the fragrance pens, you can also use essential oils, for example.

The scents that have been chosen by Dr. Hummel are rose, eucalyptus, lemon (lime) and clove. As the flavors have been classified into sweet, bitter, sour and salt, attempts have also been made to classify odors. In 1916 Hans Henning tried to divide the scents into 6 categories. From this came the following types of scent (fragrance prism): flowers (like lavender or rose petals), ethereal (such as ether or cleansing liquid), resinous (such as resin or turpentine), spicy (like cinnamon or nutmeg), spoiled (such as faeces or rotten eggs) and burned (such as tar oil), the first four being closely related and depicted as the vertices of a plane of a prism (see image). This is also called the odor prism.

The by Dr. Hummel selected scents for the 4 sticks are based on these scents:

  • Flowers: rose
  • Fruity: lemon
  • Spicy: clove
  • Resinous: eucalyptus

The effect of smell training

If you start using the markers, chances are that you will not notice an odor in the beginning. However, it is important to focus on the little smell that you may smell. Twice a day you must smell the markers with the 4 scents intensively. In total, this will take about a few minutes per day. Take a small break between the different scents so that your sense of smell can really see the difference between the scents.

Postviral patients

For post-viral patients it may be that the perception of odors is strongly disturbed. This is also known as parosmia. In this case, the smells that you observe will differ greatly from what you expect to smell. This is normal though it can be very frustrating. The best advice for parosmia is to keep the fragrance training going. Stimulation of the olfactory organ is therapeutic and will speed up the recovery process.

Period of the training

To notice the effect of the odor training, you must carry out the training for several months. Various studies have shown that the first result is often noticeable after 6-7 months. It is also important that you do it daily. In the morning and in the evening. Put the fragrance pens (or oils) in a handy place so that you do not forget it and you can train your sense of smell daily.

Is odor training suitable for me?

The loss or absence of the odor ability can have various causes. Some people are born without sense of smell. This is known as anosmia. Others lose their odor after traumatic brain damage, after a virus infection or a long-lasting cold. Odor training is generally suitable for all people who have some form of natural recovery to the sense of smell and can already perceive odor stimuli. Even though there are only very few scent stimuli or odor observations that do not make sense at all, this may be sufficient for the training of the odor. Odor training is not a medicine but a way to speed up and stimulate recovery. Think of it as a form of physiotherapy for the nose.

The effect of odor training has been investigated in various clinical studies. It appears that training the sense of smell is most useful for people with a post-viral loss of the sense of smell. In addition, research also points out that odor training has a positive effect on the development of the sense of smell in traumatic brain injury. In case of traumatic brain injury, the effect depends on how serious the original injury was. In all cases it is advisable to start the odor training as soon as possible after the loss of the odor. Even in cases of anosmia and in post viral patients who do not have any sense of smell, it may be useful to perform the odor training.

How does the training work?

Odor training stimulates the olfactory part in the brain. Clinical studies have shown that people who have performed the odor training have improved sense of smell compared to people who did not perform odor training. The participants of the study had to perform an identification and a discrimination odor test. From this came the stronger from the test with the people who had trained their sense of smell. In this study, a part of the participants was performed the odor training with strong smells and in addition a part of the participants the training with less strong odors. This showed that the group with the strong smells had better results with the smell tests. This shows that the concentration (strength) of the odors is very important. Using the standardized fragrance pens from Burghart, the user is sure of a correct concentration of fragrance. In addition, the fragrance pens are also provided with a best-before date so that you can be sure that the pens are still reliable and usable.

An interesting interview with Nancy Rawson about what exactly happened during odor training can be read here. A randomized, controlled multicenter study shows that patients with a persistent postinfectious olfactory dysfunction (PIOD) benefit from that olfactory training with an evidence level 1b. The study was carried out using the Burghart “Odour-Quartet”. Therefore the product is suitable for training olfactory abilities.The study is listed on the PubMed site at 23929687

Keep track of the progress

It is advisable and interesting to keep a log of the odor training. Make notes of what you observe so that you can observe any progression. This does not have to be daily but only once a week or 2 weeks is more than enough. It is important that you have patience and perform the training consistently. The nerves that repair the olfactory system, unfortunately, only slowly, so that patience and perseverance are important.

Professional advice

Do you have an odor deviation and are you unsure what is going on? Then contact your doctor for further advice. There can be various causes for the loss of sense of smell and can have a major impact on your health. It is possible that your condition (such as anosmia) is not recognized by a doctor that causes frustration. It is therefore advisable to delve into odor loss before you visit your doctor or general practitioner. The University of Dresden has prepared an information brochure for patients with useful and reliable information.

Tips for smell training

  • It is important to smell the different scents 2 times a day. Preferably in the morning and evening.
  • Relax and take a breath in a natural way.
  • Do not smell excessively hard or too long. 10 seconds per fragrance is sufficient.
  • Try to smell other things besides the 4 scents. For example, herbs, flowers in the garden or perfumes. Everything that is safe to smell helps to stimulate the sense of smell.
  • Continue the training, do not stop. In some people the first effect is noticeable after a few weeks, but in other cases it can take months. Unfortunately, a positive is not insured for everyone, but it is worth a try. Good luck!

Order smell training sets

Through our webshop you can order the official Duft Quartett (smell quartet) but also training set with 4 essential oils. Each set will be delivered in a box with a manual. We have these sets available from stock and can be shipped worldwide.

Types of smell disorders

The following olfactory disorders can be distinguished:

  • Anosmia: the total loss of the sense of smell. A distinction can be made between selective and complete anosmia. As the name suggests, selective anosmia is about not being able to smell certain odors. With complete anosmia, the person will no longer be able to perceive any odor.
  • Hyposmia: a reduced sense of smell. This is a quantitative olfactory disorder and occurs in different grades: mild, moderate and severe. This form of sense of smell loss often occurs with aging and is not reversible.
  • Parosmia: one this is a qualitative olfactory disorder in which odors are still observed but in which the smells are registered in a different way than usual. When registering the odors at parosmia, a distinction can be made between:
    • Euosmia: smells are perceived as pleasant smells
    • Troposmia: odors are perceived as dirty or unpleasant odors
  • Hyperosmia: this is the case when a person perceives odors excessively. The smells are observed correctly but at a higher intensity.
  • Agnosmia: odors are observed but the person is unable to name these odors.

Taste disorders

In addition to odor disorders, there may also be a taste disorder. Flavor disorders are less common than olfactory disorders. A taste disorder can be caused by damage to the face or taste buds. This can be caused by, for example, an operation, infection or trauma.

Because scents have a great influence on taste, many people who have a smell disorder think they also suffer from a taste disorder. A reduced sense of smell is often mistakenly confused with a reduced taste. When we talk about taste, we mean the basic tastes sweet, sour, sweet and bitter. In addition, there is also a fifth taste to appoint: umami. Umami is often described as savory.

The following taste disorders can be named:

  • Ageusia: a person can no longer perceive 1 or more basic tastes. In this case, there is a lack of taste. This disorder can be congenital and is then known as congenital ageusion.
  • Hypogeusia: this involves a reduced taste. A common cause of this disorder is a reduction in saliva production (xerostomia) but is also common in the elderly. Due to aging, the sensitivity of the taste buds will decrease.
    Phantom fusion: tastes are observed without stimulating the taste. This is like a taste hallucination. This is often caused by medication use, for example the person takes on a metallic or salty taste in the mouth without stimulus from outside.
  • Parageusia: tastes are still observed but they are mistakenly observed. This can lead to a taste of dirty while it should have been a normal taste. A misinterpretation of taste. It is striking that it mainly concerns dirty tastes with normally pleasant flavors, this is known as dysgeusia.
  • Hypergeusia: an overly strong perception of taste. You often see this as a side effect of a medical treatment. The person generally has a hypersensitivity to 1 of the basic tastes. This disorder often disappears after the end of medical treatment.
  • Gustatory agnosia: tastes are observed but the person can not name the flavors.

Taste strips

For taste testing we deliver the Burghart taste strips. These strips can test on the basic flavors sweet, bitter, salt and sour, but there are also additional strips available for the taste umami.