Bite Counter
It is a common fact that people often grievously underestimate the amount of food they eat. Working much the same way as a pedometer, the Bite Counter promotes awareness of how much you eat so that you can make adjustments accordingly. It costs about $800 USD, so it probably won't be the first choice for the casual dieter, but it could be very helpful to people with more serious weight issues. It also has an alarm that will sound if you go over your self-set bite limit.
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