A new study has examined why some people have moved away from the religion they were raised in, while others continue to identify with their childhood faith into adulthood.
The Pew Research Center found that decisions about religion are often made early in life and tend to last, with most people leaving faith before the age of 30.
The findings draw on data from Pew’s Religious Landscape Study from 2023–24, which surveyed 36,908 US adults, alongside an American Trends Panel survey of 8,937 adults carried out in May 2025.
The research showed that 35 per cent of US adults no longer identified with the religion in which they were raised. By contrast, 56 per cent continued to affiliate with their childhood faith, while nine per cent reported having no religious upbringing and remaining unaffiliated.
Among adults who stayed within their childhood religion, belief was the dominant factor. Nearly two-thirds said belief in their religion’s teachings was a major reason they remained affiliated, while many also cited spiritual fulfilment and a sense of purpose in life. Social and cultural factors, such as community, custom or familiarity, were less influential.
Christian motivations varied by tradition. Protestants who remained affiliated most commonly pointed to belief in doctrine, while Catholics were more likely to emphasise spiritual fulfilment.
For those who left their childhood religion, many reported losing belief, gradually disengaging, or finding religion less important over time. Others cited disagreements with religious positions on social or political matters or concerns about misconduct by religious leaders.
The study also found that childhood experience played a decisive role. Adults who recalled positive early religious experiences were far more likely to remain in their faith later in life, while negative experiences were strongly linked to becoming unaffiliated.