A new Pew Research Center report has found that Muslims are the fastest-growing religious group worldwide, with a substantial increase in followers from 2010 to 2020.
The study highlights that the global Muslim population expanded by 347 million, driven primarily by natural demographic growth rather than conversions.
In comparison, Christianity grew by 122 million during the same period, but the percentage of Christians relative to the world population decreased.
Despite this decline, Christianity still maintains its status as the world’s largest religion, boasting approximately 2.3 billion adherents, which accounts for nearly 29% of the global population.
Pew’s Global Religious Landscape report, released recently, is an updated edition of their demographic analysis on religious groups, tracking changes from 2010 to 2020.
Conrad Hackett, a senior demographer at Pew Research Center, explained that various demographic factors—such as age structure, fertility rates, mortality rates, and education—play critical roles in shaping the future size of these religious groups.
The study also examines the impact of religious disaffiliation and population growth on the global religious landscape.
The rise in the Muslim population is particularly pronounced in regions with high growth rates, including the Middle East-North Africa region, where Muslims represent a remarkable 94.2% of the population.
In sub-Saharan Africa, Muslims constitute 33% of the population, with the Asia Pacific region showing the most significant growth in Muslim numbers, increasing by 16.2% from 2010 to 2020.
While there is a notable increase in the Muslim population, Christianity saw a 1.8% decline largely due to higher population growth among non-Christians.
The decline in Christian numbers is evident in areas such as Europe, North America, Australia, and New Zealand.
Christianity remains the primary faith globally, except for the Asia-Pacific and Middle East-North Africa regions, and now stands out as the most geographically dispersed religion.
Interestingly, the study indicates that the religiously unaffiliated group has emerged as the third largest demographic, making up 24.2% of the global population.
In many European and North American countries, as well as in Australia and New Zealand, a trend of disaffiliation is evident, where many who were raised Christian no longer identify with any religious group.
This shift has significantly influenced the world Christian population.
Hackett noted that many individuals raised as Christians are transitioning to identifying as non-religious as they reach adulthood.
For the first time, Pew’s research included tracking religious switching patterns across various countries, analyzing data from 117 nations pertaining to individuals aged 18 to 54 regarding their faith affiliations from birth to adulthood.
In North America, the religiously unaffiliated population surged by 13 percentage points between 2010 and 2020, reaching 30.2%.
Latin America-Caribbean saw an increase of 4.1 percentage points in the unaffiliated population, while Europe experienced a rise of 6.6 percentage points, reaching 25.3%.
The Asia Pacific region is home to the largest number of religiously unaffiliated people, with 78% of this population residing there.
China alone accounts for 67% of the worldwide unaffiliated population, though capturing the complexities of religiosity within the country poses challenges for researchers.
Buddhists in East Asia are experiencing a similar trend, facing an increase in disaffiliation rates.
According to the study, this demographic is unique as it represents the only religious group with fewer members in 2020 than in 2010, having declined by 19 million.
However, the report points out that Buddhist population estimates may not fully illustrate the religion’s influence, as many participants engage in Buddhist practices without formally identifying as Buddhist.
Hindus, representing 14.9% of the global population, are the fourth-largest religious group, predominantly residing in India (95%).
There was also a notable 62% increase in Hindu numbers in the Middle East-North Africa region, primarily fueled by migration, along with a 55% increase in North America.
Lastly, the Jewish population, the smallest religious group included in the study, grew by 6% from about 14 million to 15 million between 2010 and 2020, maintaining a steady proportion of 0.2% of the global population.
Notably, 45.9% of Jews reside in Israel, marking the highest percentage found in any single country.
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