India is set to surpass China as the world's most populous country -- and much sooner than previously thought.

But by 2022, India's population will draw even with that of China, at 1.4 billion people, and then exceed it.

If the data proves correct, India will become the world's most populous country six years earlier than previously estimated.

According to the forecasts, India will have 1.5 billion people by 2030 and 1.7 billion by 2050. The population of China, meanwhile, is expected to remain stable until the 2030s, and then decline.

The population boom could pose certain challenges, and have a major impact on India's economy, which is already growing faster than that of China. To support population growth, India needs to modernize its farm and food delivery systems, for example. Transportation improvements would also help relieve worries.

Overall, the UN expects the world population to increase by 1 billion over the next 15 years, reaching 8.5 billion by 2030. The number is forecast to hit 9.7 billion by 2050 and 11.2 billion around 2100.

These countries will have the largest populations in 2030:

1. India (1.53 billion)
2. China (1.45 billion)
3. United States (356 million)
4. Indonesia (295 million)
5. Nigeria (263 million)
6. Pakistan (245 million)
7. Brazil (229 million)
8. Bangladesh (186 million)
9. Mexico (148 million)
10. Russia (139 million)