It is not primarily the beliefs of a group that make it toxic, but rather the level of isolation, fear, and pressure that individuals experience:
Can people come and go freely, change their minds about membership and express doubt or criticism?
Are members allowed to have lives, friends and interests outside the group? Or is it an "all-or-nothing" proposition, where the group demands absolute loyalty and devotion?
Do members have to give up nearly every part of themselves to belong? Are they made to feel guilty if they take care of their needs?
How do coercive groups work?
The main areas of a person's life are controlled in order to bind members, which can lead to unhealthy attachments.
Many different theories have been developed to explain group control: