The French fries you eat at McDonald’s are grown by Bill Gates

They might be better known for their philanthropic work, but Bill and Melinda Gates are closer to you than you’d think.

In fact, the multi-billionaires are responsible for one of the world’s most popular fried foods – the humble McDonald’s French fries.

Potatoes used by the US fast-food giant, carrots and onions are among the fresh produce grown across farmland owned by the Gates, according to recent data gathered by The Land Report and NBC News.

In less than a decade, the couple (who recently announced their divorce), have invested in more than 108,900 hectares of farmland across 18 states in the US.

Phenomenally, the total land size owned by the Gates duo is almost the size of Hong Kong.

From soybeans, corn, cotton and rice grown across about 28,300 hectares in Louisiana to producing potatoes across more than 5,700 hectares of land in Washington – fields so huge that they are visible from space – the agriculture investment portfolio makes Bill Gates the largest private owner of farmland in the US.

With assets reportedly totalling more than US$690 million, the Microsoft Co-Founder took to Reddit in March to explain why he’s delved into agriculture.

"My investment group chose to do this," he wrote. "It is not connected to climate."

While the billionaires are profuse advocates for climate action, the farming venture was seemingly an investment decision. The acres were purchased through a constellation of companies linking to the Gates’ investment group, Cascade Investment.

"The agriculture sector is important," he wrote. "With more productive seeds, we can avoid deforestation and help Africa deal with the climate difficulty they already face.

"It is unclear how cheap biofuels can be, but if they are cheap it can solve the aviation and truck emissions."