对于角逐国际足联世界杯的国家来说，体型并不总是意味着目标和荣耀。

The planet’s biggest sporting event – the FIFA Men’s World Cup – is now underway, drawing a television audience of billions and a stadium audience of millions.

There’s no shortage of other impressive statistics to illustrate the scale of the tournament’s 23rd edition. A record 48 teams have begun playing 108 matches across 16 venues in three North American countries, competing for a record prize pool of nearly US$900 million.

For demographers, a look at the competing countries also offers a snapshot of a world undergoing profound change.

And it raises an intriguing question: how much do factors such as a country’s population size and age alone weigh on chances of success?

Why size isn’t everything

The spread of countries represented this year is remarkable, as is the age range of talent taking to the field.

Portugal’s Cristiano Ronaldo is still competing at 41, while Spain’s 18-year-old Lamine Yamal arrives as one of the game’s brightest young stars after helping his country win the European Championship in 2024.

Côte d’Ivoire has brought the youngest squad, with a median age of 25.4, while Iran fields the oldest at 31.3. Those figures might mirror trends at home: Côte d’Ivoire’s median population age is just 18.1 years, compared with 34.3 in Iran.

Still, the relationship between a country’s football team and the age of its population isn’t always straightforward.

Japan has the oldest population of any nation at the tournament, with a median age of 49, while its squad – widely regarded as one of the strongest in Asia – has a median age of just 27.4.

That puts it within a statistical sweet spot in the tournament’s history: the optimum average age for a world cup finalist has been cited at between 26 and 28.5 years old.

Population size might also seem like an obvious advantage at a world cup.

More people should mean a larger talent pool to draw from and, indeed, one recent analysis suggested this to be a top predictor for world cup qualification.

Brazil would certainly fit this theory. Home to more than 211 million people, it is the second most populous nation at the tournament and its most successful, with five world cup titles.

At the same time, size can’t ensure victory. The world’s two most populous nations, China and India, have never qualified for a men’s world cup finals, while the United States has reached only one semi-final despite its population exceeding 340 million.

The same statistical models that highlight the power of population also reveal glaring anomalies. Italy, boasting a massive reserve of talent, failed to make the cut.

Then there are those small nations that seemingly punch above their demographic weight.

Curaçao, with a population of just 185,000, is the smallest nation ever to qualify for a world cup. Every member of its squad plays professionally overseas – many in the Netherlands – illustrating how football talent can be developed far beyond a country’s borders.

Another stand-out is Uruguay. With a population of just 3.4 million, the South American nation has won the world cup twice and remains one of the sport’s great overachievers.

Population may help produce football talent, but the world cup suggests other factors have an important part to play.

Demographics and dividends

As recent analyses have suggested, wealth, coaching systems and long-established football cultures can be just as important as the size of a country’s player talent pool.

The same principle applies away from sport. Demographers have long argued that a country’s prospects can be influenced not just by how many people it has, but by the age structure of its population and how effectively it develops its human capital.

Many of the tournament’s countries with younger populations – particularly across Africa, Asia and the Pacific – have growing workforces and a large share of young people entering adulthood.

Economists refer to the opportunities created by a relatively large working-age population as the “demographic dividend”.

Migration is also becoming increasingly important. Across much of Europe, immigration now accounts for a significant share of population growth, helping offset labour shortages and population ageing.

The world cup reflects this reality, with many national teams drawing on players whose family histories span multiple countries.

But neither a youthful population, strong migration nor sheer population size guarantees success – whether on or off the pitch.

The key, if this world cup offers countries any lesson in demography, is investment in people.

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.