The main function of air ionizers in general and TEQOYA ionizers, in particular, is to diffuse negative ions capable of purifying the surrounding indoor air of different pollutants that are harmful to health. Present in large quantities in the purest natural places on earth, negative ions are beneficial to humans and the planet. Ok, but... where to find them? How do they act... and what are the effects?
As a surfer, I always try to breathe the purest sea air possible. Because of its richness in mineral salts and negative ions, sea air has many health benefits. The swell, the waves, and the winds increase the concentration of these elements. To reproduce these effects in the indoor air of my medical practice, I decided to test an ionizer device that, in addition to the expected effects on well-being, reduces the presence of microbes, micropollutants, and allergens in the indoor air that my patients breathe.
Guillaume Barucq, General practitioner and author of the books "Surf Therapy" et "Detoxification"
The air is naturally ionized, balancing positive and negative ions in natural environments.
In the purest natural spaces, we can find large quantities of negative ions: at the foot of waterfalls, for example, the bursting of water droplets releases electrons (a physical phenomenon called the Lenard effect) which ionize oxygen (O2- ion, see below) or in the mountains, by the sea, in the forest, in the sun...
Have you ever felt the calm before the storm? And why a sudden feeling of peace at the seaside? This is where ions come into play and influence our physiology.
Some studies have established that negative ions are beneficial to our health: they improve our sleep quality, our body tissue oxygenation, our concentration, and our mood... Negative ions would also make us less vulnerable to stress. 
The positive ions are present in polluted environments, while negative ions tend to disappear, particularly in closed spaces where the air is conditioned (i.e. heat is transferred between the air and the ceiling). Some devices can increase positive ions, such as AC, photocopiers, electronic cards, or screens.
The effects of positive ions on human health start now to be known: increased irritability, migraine crises, or even thrombosis in response to changes in the electrical charge of the atmosphere that follow meteorological upheavals. 
Researchers found that these electrical charges (aka positive ionization) generated by weather change produce a release of serotonin in our body. They also identified three types of weather sensitivity responses:
Contrary to what their name suggests, negative ions have a positive effect on the air, human health, and the feeling of well-being. They enter the body mainly through the respiratory and skin pathways. They help the exchanges between cells and the penetration of oxygen into the lungs.
Negative ions also have the particularity of purifying the atmosphere from pollutant particles. Salty sea air - much purer than urban air - has about 100x fewer germs. 
In the great Eastern cultures, Chinese and Indian, a vital principle - also called breath or vital energy - has a central place in the foundations of medicine, health care, and personal development. In Chinese medicine, this principle is called Qi: the base of the Yin-Yang energies of the body.
According to the foundations of Yoga, Prana is the vital energy that circulates in the universe and all living beings. One of the most important sources of vital Prana is the atmosphere, and the breathing practices of Yoga consist in absorbing this vital energy from the air. 
Our body absorbs electricity from the atmosphere, uses it, and then releases it via skin pathways: the more active this metabolism is through the absorption of negative ions and the release of excess electrical charges, the more "alive" and the healthier we will feel. The negative ions, therefore, have a beneficial impact on respiratory levels.
For yogis, the nose is the main organ for the absorption of Prana. Air would be our main food: we breathe about 12,000 liters of it every day, so it might as well be healthy!
In 2013, an Italian research team made an interesting discovery of the influence of negative ions on human psychophysiology: they have a beneficial effect on the treatment of mood disorders (reduction of symptoms) and improve cognitive performance. "There is single variability. Some people are more receptive than others to the lack of negative ions. They may have various disorders, for example, insomnia, fatigue, irritability, lack of concentration, dark thoughts, headaches, respiratory discomfort", declares Dr. Robert. 
British researchers at the Institute for Sport and Exercise Sciences in Liverpool exposed men to negative ions to measure their physiological responses: body temperature, heart rate, and breathing, at rest and during exercise. Negative ions significantly improve all physiological states, especially during the resting period. Negative ions improve cardiac function by adjusting heart rate and blood flow velocity, improving sleep quality, alleviating angina, and normalizing blood pressure. 
Some types of air ionizers have been proven to remove airborne particles, dust, cigarette smoke, pet dander, pollen, mold spores, bacteria, and viruses.
With the help of a powerful air ionizer, you can have the following results: in 30 minutes, the elimination of 97% of the particles of 0,1 microns (ultrafine particles) and 95% of the particles of 1 micron (PM1) in your indoor air. Moreover, the negative ions reduce the concentration of airborne particles (PM1): in 2 hours, the elimination of 95% of bacteria in the air according to laboratory tests. In an experiment carried out in a controlled environment, air ionization also reduced the concentration of fine particles (PM10) by 70% to 75%. 
The relation between air ionization and respiratory diseases can be deduced from the action of ions on pollutant particles: the frequency or severity of crises is reduced by the decrease of the triggering or aggravating factors of chronic respiratory diseases, which are mostly particles and allergens transported by the air.
Epidemiological studies have shown an influence of negative ions on asthma, although there are no recent clinical studies on this subject. Cossec in France reports the results of the treatment of a group of 30 patients treated on a long-term basis (one and a half years) and at high concentrations (of the order of 100,000 ions/cm³ and more at a distance of 60 cm from the ionizer) that led to a significant reduction in prescriptions of asthma drugs: theophylline derivatives (-43%), corticosteroids (-44%), and antiallergic drugs (-71%). 
The clinical results showed that, after inhalation of negative ions in high doses for 30 minutes, we have a 20% increase in oxygen absorption and a 14.5% increase in carbon dioxide emission. Negative ions would therefore be active in the normalization of pulmonary functions, thus helping asthmatic patients.
The offer of air Ionizers has increasingly developed in the category of air purifiers. No doubt that air ionization is an effective air purification technology. However, if not properly controlled, it can emit ozone. Before purchasing an air ionizer, be sure it does not emit any ozone! This gas is harmful to your health and would cancel all the benefits of negative ions.
Rest assured that TEQOYA ionizers are 100% safe. They are the only ones that do not emit ozone: independent laboratory tests that have measured ozone within a few centimeters of a TEQOYA unit report a density of less than 2 ppb, which is about as accurate as measuring devices.  TEQOYA air ionizers are also energy efficient (1.5W, or less than 5 euros per year). You can sleep tight... and breathe healthy air!
 International Journal of Molecular Science - Temasek Life Sciences Laboratory, Singapore (2018). Negative Air Ions and Their Effects on Human Health and Air Quality Improvement. Disponible sur : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6213340/
 Nutrition Review (2010). Les bienfaits sur la santé des ions négatifs. Disponible sur : https://www.ionisation.be/Les_bienfaits_sur_la_sante_des_ions_negatifs_-_Nutritionreview_2003.pdf
 Research in Psychology and behavorial science - Department of Neurosciences, University of Parma, Italy (2013) . There's Something in the Air: Empirical Evidence for the Effects of Negative Air Ions (NAI) on Psychophysiological State and Performance. Disponible sur : https://www.researchgate.net/
 Apnee Savoie (2012). André Van Lysebeth, le yoga, Pranayama, les ions négatifs et l'apnée. Disponible sur : Archives | APNÉE SAVOIE (apnee-savoie.com)
 National Library of Medicine (1993). An investigation of the effects of negative air ions on responses to submaximal exercise at different times of day. Disponible sur : An investigation of the effects of negative air ions on responses to submaximal exercise at different times of day - PubMed (nih.gov)
 Emersum & Université de Rome (2020). Effect of ionization on nebulized droplets containing Influenza A/H1N1/ PR8 virus. Disponible sur : TEST_REPORT_H1N1_EMERSUM_SAPIENZA.pdf (teqoya.fr)
 TEQOYA (2022). Revue biblio : les bienfaits pour la santé des ions négatifs. Disponible sur : Revue biblio : les bienfaits des ions négatifs? (teqoya.fr)
 CERTAM (2016). Mesure du potentiel oxydant d'un purificateur d'air TEQOYA par résonance paramagnétique électronique. Disponible sur : rapport_TEQOYA_Certam_potentiel_oxydant_V1.1.pdf
Natural environments are rich in negative ions. This is precisely the principle on which the air ionizer is based on. However, do you know how this technology manages to capture the pollution particles contained in the indoor air to purify your home?
In December 2019, a respiratory virus of the Coronavirus family appeared in the Wuhan region of China and has now spread to all continents.
Purifying indoor air while protecting your health and the planet is possible! Say goodbye to filters and make way for negative ions: choose an eco-responsible air purifier that will easily reduce energy and resource consumption.