Scientists have long known about the ability of negative air ions to purify air by removing particulate matter in air pollution. In recent studies, negative air ions have also been shown to reduce stress and depression, regulate sleep and mood, boost focus and immune function, and kill or inhibit the growth of harmful bacteria, viruses and mould.

Negative air ions are molecules or atoms floating in the air that carry an electron. Natural phenomena such as thunderstorms, ultraviolet rays from the sun, crashing water in waves and waterfalls, and plant growth, all discharge negative air ions. This explains why people feel in a better mood when they’re at the beach, or after a thunderstorm.