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I am not sure to get the question. Dark matter can interact with normal matter, making it recoiling. This recoil can be observed 9this is the main consequence). In terms of consequences on humans, if this is the question, there is none (like the interactions of neutrinos with humans, but at a much much much reduced pace). The same holds for Earth as the interactions are at the end of the day very local.

Thanks for welcoming me back :)