“LED bulbs can bring on feelings of dizziness and pain within just 20 minutes of switching them on, an expert has warned. …Flickering lightbulbs disrupt the control of this eye movements, making the brain use more energy to work harder, which has been linked to headaches.”
http://www.dailymail.co.uk/health/article-4739766/Low-energy-LED-lightbulbs-giving-HEADACHES.html
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