Historically, I’m guessing Christianity probably used to be the world’s fastest growing religion but recent studies predict, if trends continue, Islam will soon be the world’s largest and fastest growing. Reasons for this include that although the world’s population is estimated to grow 32%, the population of Muslims is expected to increase by 70%. Part of the growth can be accounted for by the fact that Muslims have more children than members of the seven other major religious groups.
Also the Muslim population “is helped by the fact that Muslims have the youngest median age (24 in 2015) of all major religious groups, more than seven years younger than the median age of non-Muslims (32).” In addition, ”religious switching – which is expected to hinder the growth of Christians by an estimated 72 million between 2015 and 2060 – is not expected to have a negative net impact on Muslim population growth”.
