Blue light is needed for your good health. It boosts alertness, helps in memory and cognitive function and elevates mood. It regulates circadian rhythm. The body’s natural wake and sleep cycle. Exposure to blue light during day time hours helps maintain a healthful circadian rhythm. Too much exposure of blue light in the night can disturb the wake and sleep cycle, leading to problems sleeping and daytime tiredness. Not enough exposure to sunlight in children could affect the growth and development o the eyes and vision. Early studies show a deficiency in blue light exposure could contribute to the recent increase in myopia. Recent research suggests that exposure to blue light before sleep may distort your natural rhythm and cause an inability to fall asleep.