In Israel, the soldiers' performance, such as alertness, response time, strength, decreases when the dry, dusty and hot wind called “Sharav” blows in from east and researchers found that the wind contains high concentration of positive ions, which increase the level of serotonin. Serotonin is a neurotransmitter and both high and low levels of serotonin are associated with many disorders, such as fatigue, depression, irritability, migraine. Many studies show that negative ions suppress overproduction of serotonin and normalize the serotonin levels.
In the former Soviet Union, negative ions were used to improve the performance of Olympic athletes. They were trained in rooms equipped with negative ion generators and their performance increased greatly. Afterward more studies have been performed to increase the productivity of factory workers with negative ions, and the results have been good, too.
Also exposure to positive ions makes red blood cells stick to each other and makes it harder to flow through blood vessels. If this state continues, one may suffer heart attack or any other problems. On the contrary, negative ions separate the red blood cells from each other and promote good blood circulation. Higher concentration of negative ions takes less time to result in this, and lower level needs more time, but too many negative ions may have side effects, such as nosebleed, and too little take too much time, so the right amount is needed for the best result. The following pictures show negative ions' effect on red blood cells.
Effect of negative ions on red blood cells after a 30-minute exposure
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| Before | After |
Left: After watching the TV for 1˝ hours. It clearly shows red cells are all stuck to each other.
Right: After another ˝ hour watching the TV but with a negative ion generator on. You can see many red cells are separated and are on their own.