North Korean leader Kim Jong Un's 20kg weight loss amid food shortages, residents told to eat less

North Korean leader Kim Jong Un delivers a speech on October 10. Photo / AP

After North Korea's authoritarian government told residents to "eat less" to combat a national food shortage, it's been revealed Kim Jong Un has lost 20kg.

The North Korean dictator's health has long been a point of speculation – and his noticeably thinner appearance in state media photos and videos have led many to wonder if he's unwell.

But during a closed-door parliamentary briefing on Thursday, South Korea's National Intelligence Service said the 37-year-old had no apparent health problems and his weight loss was likely the result of efforts to improve his physique.

According to several of the session's attendees, politician Kim Byung-kee said Kim's weight had fallen from about 140kg to 120kg.

Experts first expressed their surprise at the dictator's changed appearance when he was the guest of honour at a military parade in Pyongyang last month.

"It's striking how much healthier Kim Jong-un is looking in these photos from yesterday," North Korea-focused journalist and researcher Martyn Williams wrote on Twitter at the time.

"However he is doing it – and there are theories – he looks a lot better than he did a few months ago."

Hong Kong-based journalist Ryan Chan also chimed in, writing: "I have never seen Kim Jong-un in such a healthy body shape before."

This combination of file photos provided by the North Korean government, shows Kim Jong Un at Workers' Party meetings in Pyongyang on February 8, 2021, left, and June 15, 2021. Photo / AP

Kim's physical transformation comes amid fears North Korea's food shortage could last for at least the next three years.

Having long suffered from food insecurity, observers say government mismanagement of the economy has been exacerbated by the Covid-19 pandemic, natural disasters and international sanctions.

As a result, sources told Radio Free Asia that residents are being told to eat less, leading them to feel "great despair".

"The food situation right now is already clearly an emergency, and the people are struggling with shortages. When the authorities tell them that they need to conserve and consume less food until 2025," they said.

The Sun reports Kim has signed an edict telling his starving countrymen to feast on black swan – claiming the bird's meat fights cancer.

"Black swan meat is delicious and has medicinal value," a party-run news outlet said this week, adding that the bird's breeding on an industrial scale will actively contribute to improving people's lives.

The propaganda says the meat has more protein and contains rare health substances such as immunoglobin, linoleic acid and compounds with "anti-cancer" properties.

A new black swan centre was recently opened at a duck farm on the nation's east coast.