The harmful positive ion (kation) is a particle that loses an electron. The healthful negative ion (anion) gains an electron in the valency orbit; that is it increases the ability to absorb and utilize oxygen and reduces any excess of harmful serotonin.
These two small invisible electrified particles have an effect on our physical and mental well-being and we are constantly bombarded with negative and positive ions (eg. polluted air). The negative ions make us feel good, they destroy harmful bacteria. The positive ions make us feel bad (TV. screen produces positive ions).
If the positive ions occur naturally in sufficient numbers, for instance during the onset of the commonly known hot and dry desert winds, the winds cause depression, nausea, insomnia, irritability, lassitude, migraine, asthma attacks, and also affect the normal function of the thyroid glands. Biochemically speaking, the body becomes exhausted and this can lead to an increase in accidents, violent crime and suicides. These can be counteracted with the beneficial negative ions.
Negative Ions are the good ions. Positive ions are depleting. You want negative ions NOT positive ions. The units on the market that claim their machine can create more negative ions or positive ions depending on which mode the unit is set too is not only inaccurate but why would you want positive ions?
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SOURCE: Negative Ion Report: The CBS Nightly News, Feb 14, 1995
ANSWER: NEGATIVE ION