Paranoid North Korean dictator Kim Jong-un has medical experts analysing each lettuce leaf he eats for "germs, toxins and other harmful elements".

Instead of just relying on farm inspections, the secretive ruler's food needs to go through an 'Escort Bureau' in order to receive the green light for his consumption.

This means a meticulous screening process using a microscope takes place on the specially built Pyongyang farm which grows the 32-year-old's vegetables.

An anonymous Pyongyang source told Daily NK, based in South Korea, about the lengthy process the leader's food must go through before it is approved.

They said: "Inspections for produce for Kim Jong Un coming out of the 6.17 Farm in Pyongyang's Yongsong District have become stricter.

"The produce that will go to Kim Jong-un is first washed thoroughly.

"It then goes through inspections by specific departments before being handed over for an executive examination and is finally being shipped out as a grade (8 or 9) product.

"But recently, units under the Escort Bureau tasked with transporting the produce have been conducting an additional final screening.

"Microscopes are used to look for germs, toxins, and other harmful elements."

Only those with suitable 'songbun' – which means family links and loyalty to the reigning Workers' party of Korea - are allowed to work on the 6.17 farm.

The source continued: "Inspectors are Pyongyang citizens with immaculate songbun and status who have graduated from Pyongyang Medical University; they'll spend minutes on one single leaf of lettuce."

According to Daily NK, the farm was built in 1980s for his father, Kim Jong-Il, and produces superior fruits and vegetables in greenhouses scattered across an estate of 6 hectares in the mountains.

There are five units, each comprising approximately 80 workers, tasked with growing different produce.

Kim Jong-un became the leader of the highly secretive state in 2011, having inherited the position after his father died.

In the last decade North Korea has been mired by poverty and economic ruin, and a devastating famine in the 1990s which killed between 240,000 and 3.5 million citizens through mass starvation.

On Thursday 9 July South Korean officials stated that they believed Kim Jong Un has executed 70 officials since taking power, the Associated Press (AP) reports.