FACT:
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blue tooth frequency 2.402 Giga Hertz
GSM frequency in india ranges from 900 to 1850 mhz.
microwave cook food "optimally" at a frequency 2.45GHZ
so using a cell phone or headset near the ear means essentially you are cooking your Brain.
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I suggest you use a wire headphone (safe )and keep the mobile at distance away from head, it will solve your head ache problems as well as future brain related side effects or tumours.
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