A small number of people do seem to have a pimple like reaction to certain food groups, chocolate is one, but more commonly, nuts.

有一小部分人确实好像因一些食物而产生类似粉刺的反应。巧克力是其中之一，但更常见的是坚果。

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Seven years ago Los Angeles high school social studies teacher Joseph Rick spotted a purple pimple on the small of his back.

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