I guess for proof all we need to do is point to this currant batch of Governing Body members and we can rest our case.
http://www.scientificamerican.com/article/religious-experiences-shrink-part-of-brain/
In this study, Owen et al. used MRI to measure the volume of the hippocampus, a central structure of the limbic system that is involved in emotion as well as in memory formation. They evaluated the MRIs of 268 men and women aged 58 and over, who were originally recruited for the NeuroCognitive Outcomes of Depression in the Elderly study, but who also answered several questions regarding their religious beliefs and affiliation. The study by Owen et al. is unique in that it focuses specifically on religious individuals compared to non-religious individuals. This study also broke down these individuals into those who are born again or who have had life-changing religious experiences.
The results showed significantly greater hippocampal atrophy in individuals reporting a life-changing religious experience. In addition, they found significantly greater hippocampal atrophy among born-again Protestants, Catholics, and those with no religious affiliation, compared with Protestants not identifying as born-again.
The authors offer the hypothesis that the greater hippocampal atrophy in selected religious groups might be related to stress. They argue that some individuals in the religious minority, or those who struggle with their beliefs, experience higher levels of stress. This causes a release of stress hormones that are known to depress the volume of the hippocampus over time. This might also explain the fact that both non-religious as well as some religious individuals have smaller hippocampal volumes.
This is an interesting hypothesis. Many studies have shown positive effects of religion and spirituality on mental health, but there are also plenty of examples of negative impacts. There is evidence that members of religious groups who are persecuted or in the minority might have markedly greater stress and anxiety as they try to navigate their own society. Other times, a person might perceive God to be punishing them and therefore have significant stress in the face of their religious struggle. Others experience religious struggle because of conflicting ideas with their religious tradition or their family. Even very positive, life-changing experiences might be difficult to incorporate into the individual’s prevailing religious belief system and this can also lead to stress and anxiety. Perceived religious transgressions can cause emotional and psychological anguish. This “religious” and “spiritual pain” can be difficult to distinguish from pure physical pain. And all of these phenomena can have potentially negative effects on the brain.