There should be 6 1/2 to 7 1/2 heads in the height of the average caucasian. East asians have slightly larger heads, even when raised in the USA and of 'American height' this seems to be true. Comics use smaller heads - often 8 3/4 (Marvel comics standard), anime uses larger heads - 4, 5, or even in 'SD' only 2. Much modern anime however, has shifted to the 8 head ratio.

Truth has no value without backing by unfounded belief.
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