What are the effects of false news exposure on downstream trust and belief? In two online experiments (N participants = 2,735, N observations = 49,158) we investigated whether exposure to high proportions of false news could have deleterious effects by sowing confusion and fueling distrust in both true and false news. In a between-subjects design where U.S. participants rated the accuracy of true and false news, we manipulated the proportions of false news participants were exposed to (17%, 33%, 50%, 66% 83%). We found that exposure to higher proportions of false news decreased trust in the news and increased skepticism in news judgments. Across conditions, participants were more likely to mistakenly rate true news as false than to rate false news as true, and exposure to higher proportions of false news exacerbated this tendency. While the proportion of false news had no effect on participants’ overall ability to discern between true and false news, it made participants more overconfident in their discernment ability. These findings suggest that exposure to false news may have deleterious effects not by increasing belief in falsehoods, but by reducing belief in true news and by eroding trust in the news media even more.