Dr. Michael Terman
Head Colombia University - Winter Depression Unit

The benefits of exposure to relatively high concentrations of negative ions produced by high density negative ion generators have been well documented over decades. Literally dozens of studies published in respected journals have concluded that negative ions can have a profoundly beneficial effect on both the mind and body. Listed here are some excerpts from just a few of the scientific studies on the subject of negative ions.

The most recent and exciting study was published in the February 1995 issue of "Journal of Alternative and Comparative Medicine", a journal of the Colombia Presbyterian Medical Centre. The results of this study were also reported on CBS News with Connie Chung.

Researchers Dr Michael Terman (Head of Colombia's Winter Depression Dept.) and Dr Jiuan Su Terman conducted a study of the impact of negative ion therapy on people suffering from seasonal affective disorder (winter depression) - an illness that is often symptomatically indistinguishable from "all year" depression; researchers believe that the biology of seasonal affective disorder (SAD) is very similar to that of "all year" depression, hence, the same antidepressant drugs (such as Prozac) are used to treat both.

The study was conducted in double blind fashion and divided clinically depressed subjects into two groups. The subjects in the first group were treated for 30 minutes a day for 20 days with a low density ion generator that produced only 10,000 ions/cubic centimetre ( the control group). The subjects in the second group were treated for 30 minutes a day for 20 days with a high density ion generator that produced 2,700,000 ions/cubic centimetre (the experimental group). The remission or "cure" criterion used was a 50% or greater reduction in symptom frequency and severity using the SAD version of the Hamilton Depression Rating Scale.

The results of this study shocked the medical community: While a low density negative ion generator provided little benefit, a high density negative ion generator gave relief from depression comparable to that given by Prozac and other anti-depressants, without drug side effects.

Connie Chung: This is the age of wonder drugs and high-tech cures, but alternative treatments, from herbs to acupuncture, have true believers, too, even among some mainstream doctors and researchers. Latest case in point; the wintertime blue. Is it possible that changing the air you breathe can treat those negative vibes and actually relieve depression? Dr Bob Arnot has the story.

Dr Bob Arnot: If the blustery winds of winter blowing across the nation this week are bringing you down, there's a good reason. Researchers now believe that the ill winds strip away highly charged subatomic particles called Negative Ions from the air around us, contributing to a seasonal form of depression.

Ms Mahala Holmes (patient): As far back as I can recall, I had feelings of dreading winter and ... and went through this kind of depression.

Dr Arnot: Doctors at Colombia demonstrated the use of this machine to pump high-density negative ions into the air surrounding Mahala Holmes to treat her depression, known as a seasonal affective disorder.

Ms Mahala Holmes: While I was on treatment, I felt excited, I felt energised. I felt alive.

Dr Arnot: Here's why. Level of brain chemical responsible for mood, called serotonin, are often lower in cases of season depression. Serotonin levels can be elevated by increased exposure to light or by antidepressants like Prozac. Researchers say negative ions may also increase brain levels of Serotonin.

Dr Michael Terman: (Colombia Presbyterian Medical Centre): People noticed that daytime energy was returning to normal levels. They lost that pressure for increased sleep, the difficulty awakening in time to get to work.

Dr Arnot: A study in the current "Journal of Alternative and Complimentary Medicine" concluded that 58% of patients treated with high-density negative ions had significant relief of their symptoms, almost identical to the number improved with drugs, but without drug side effects.

Dr Norman Rosenthal (National Institute of Mental Health): From a scientific point of view, it's very exciting. It needs to be replicated.

Dr Arnot: The whole idea of using negative ions as a legitimate medical treatment may seem just a little bit odd. But while many doctors are still highly sceptical about alternative medicines, more and more Americans are turning to them because they haven't found the satisfaction they want from mainstream medicine. This is not the first study to prove the benefits of negative ion generators. About 15 years ago, a double blind study was conducted at the Air Force Aerospace Medical Research Laboratory at Wright-Patterson Air Force Base in Ohio. The study was published in the August 1982 issue of the prominent medical journal "Aviation, Space, and Environmental Medicine" in an article entitled "Subjective Response to Negative Air Ion Exposure". The study was conducted as follows, quoting from page 822 of the Journal:

"Procedure: One group of subjects served as controls and was confined to the test chamber for a 6 hour period under air ion conditions typical of an energy efficient building. The second group was similarly confined, but ion generators began operating 2 hours before occupancy and continued all 6 hours of confinement. Generators were masked for all indications of operation, and were also present under control conditions but not turned on. Data from both groups were collected under double blind conditions".

The results of the study were encouraging, as stated on page 823 of the journal: "Subjective perceptions of psychological state, using individual 'normalcy' as standard, reflected significant differences between control and negative ion exposure groups. Prominent perceptions reported were reductions in irritability, depression and tenseness and increases in calmness and stimulation associated with ion exposure.

For psychological state, negative ion exposure appeared associated with feeling better about self, less sensitive and more responsive or innervated (energised)". In October 1981, a journal article entitled "The Influence of Negative Air Ions on Human Performance and Mood", appeared in the respected journal, Human Factors. On page 633 of the journal, the abstract of the article reads: "44 female and 12 male 17-61 year olds were tested either in a normal ion environment (control group) or in a predominantly negative ion environment (experimental group). After a 15-minute acclamation period, subjects asserted their psychological state and completed 2 performance tasks.

Results indicate that subjects had faster reaction times and reported feeling significantly more energetic under negative air ion conditions than under normal air conditions".

Later that year in December of 1981, a study conducted at California State University, Sacramento entitled, "The Influence of Air Ions, Temperature and Humidity on Subjective Wellbeing and Comfort" , was published in the "Journal of Environment Psychology". The findings were encouraging. On Page 279 of the journal, the abstract of the article states:

"106 employees kept daily assessment records of their office environment and health over a 12 week period. Temperatures about 23 degrees Celsius were associated with increased sensations of stuffiness, discomfort and unpleasantness, but appeared to produce a decrease in the number of complaints of headaches. The office environment was found to be depleted of small air ions. The introduction of a negative ion generator increased the subject rating of alertness, atmospheric freshness and environmental and personal warmth. Ions reduced the complaint rate for headache by 50% and significantly reduced the number of complaints of nausea and dizziness".

Of course, much of the early research concerning negative ions has been conducted on animals. One of the earliest studies of the effects of negative ions was published in 1935 in the "Journal of Industrial Hygiene" in an article, "The Effect of High Concentrations of Light Negative Atmospheric Ions on the Growth and Activity of the Albino Rat". In it, researchers Herrington and Smith evaluate the effects of negatively ionised air on the activity of rats as measured by means of an activity wheel.

They found that activity increased significantly with rats subjected to a reported negative ion concentration of 1.2million ions/cc. In 1956, a researcher named J .V. Brady published a study in "Annals of New York Academic Science" which showed that the strength of the conditioned controlled emotional responses of fear and anxiety in animals can be dramatically reduced by the daily administration of the psycho active drug reserpine.

Years later in 1967, a similar study was conducted by Allan H Frey at the Institute for Research, Pennsylvania State University and published in the "Journal of Comparative and Physiological Psychology". The major difference was this time, the effect of reserpine was compared to that of negative ion treatment. The study concluded: Results of 2 experiments, the 2nd essentially a replication of the 1st, are in accordance with prediction. The inhibition of response in the animal was reduced by treatment with small negative air ions as it was with reserpine. In other words, when the animals were treated with negative ions, the animals were less inhibited-less likely to experience fear and anxiety. These results are similar to the results of experiments studying the anti-anxiety effects of tranquillisers such as Valium and Xanax.

It has also been shown that in addition to possibly having a profound effect on mood and energy, negative ions may have a strong impact on cognitive functioning. In 1965, in the journal "Psychophysiology" a study, "Behavioural Effects of Ionised Air on Rats" was published. In this study, the effects of negatively ionised air on the mental functioning of rats was tested. Researchers Duffee and Koontz reported on page 358 of the journal: "the water maze performance improved by 350%" showing a dramatic improvement in cognitive functioning.

To support that negative ions also improve the cognitive functioning of humans as well, in April of 1978, in the Science Journal "Ergonomics", a study was conducted at the University of Surrey, England and published in an article entitled, " Air Ions and Human Performance". Once again, the results were encouraging. On Page 273, the article reads:

"Studied the effects of artificial negative or positive ionisation of the air on the performance of psychomotor tasks with 45 18-26 year old healthy males...Three testing environments were used: natural, negative and positive ionisations. Negative ionisation was associated with significant increment in performance as compared to controls".