Is it possible to create a secure community forum

I am researching host providers and processes with the intent of setting up a forum for a specific community. But forum security seems to only be as strong as the security of its host server, which from the look of things isn’t encouraging. Of course there are options with higher security, but there is a trade off between security and ease of signup/usage and user uptake of the forum, where convoluted user setup can be a major impediment. Is there any way a community forum can be created that can give reasonable assurances around privacy and security for its users?