INDIA BECOMES THE LARGEST POPULATION IN THE WORLD CLAIMED BY RESEARCHERS

Yi Fuxian, a researcher's bold claim suggests India is now the world's largest country.

What's the most populous nation in the world? For years, the answer to that question was simple and rarely disputed: China. But this week an academic has sparked widespread discussion around the world by making a bold claim - that China's official population estimates were wrong and in fact India was now the world's largest country.

This potentially radical suggestion was made Monday by Yi Fuxian, a researcher at the University of Wisconsin-Madison, during an event at China's Peking University.

According to the South China Morning Post, Yi suggested that China had only 377.6 million new births from 1991 to 2016, far less than the official figure of 464.8 million. This meant that China's official population estimate, currently at 1.38 billion, was wrong, Yi said. Instead it should have been 90 million lower - a gap roughly the same as Germany and Belgium's population combined.

That would make it 1.29 billion, and lower than India's estimated 1.32 billion population, according to Yi. 

Multiple media outlets in China, India and beyond quickly picked up the news. If Yi was right, the implications would certainly be big. Not only would it mean that India had already overtaken China as the world's largest nation - something the United Nations had estimated to happen in 2022 - but that China's population growth slowdown was worse than many thought and being hidden from the public.

Reached via email, Yi said the controversy was "no surprise" to him, but added that he had already noted his belief that China's official estimates were wrong in the 2013 edition of his book, "Big Country with an Empty Nest," which took a critical look at China's family-planning policies.

In fact, Yi says he was sure the estimates were wrong far earlier. "In 2003, I knew China official announcement population data is much higher than the real population," Yi wrote from Taiyuan, China.

Among the many notable elements of Yi's claim is where he's making it from: mainland China.

The academic, born in Hunan province, had moved to the United States in 1999. After moving to take up graduate studies at the University of Minnesota-Twin Cities (he later worked as a fellow at the Medical College of Wisconsin and moved on to the University of Wisconsin Madison as a scientist in 2002), Yi quickly became a vocal critic of China's family-planning policies, including its "one-child" rule.