But experts think weight gain may be deliberate to look like late grandfather

His weight has ballooned in recent months and he now walks with a limp

He has been seen walking with a limp, raising speculation it may be gout

After more than a week of speculation, North Korea has finally admitted its 'Dear Leader' is poorly - sparking new rumours he may have gout.

Kim Jong-un, whose weight has ballooned in recent months thanks in part to an addiction to Swiss cheese, has been struck down by a mystery illness, his henchmen in Pyongyang revealed today, saying only that he was 'suffering from discomfort'.

It comes after the 31-year-old vanished from his usual role as centrepiece to the isolated country's propaganda machine after last appearing in public at a concert with his wife on September 3, fuelling speculation he is suffering from bad health.

He had been seen walking with a limp since an event with key officials in July and in a pre-recorded documentary broadcast by state media on Thursday appeared to have difficulty walking.

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Unwell? Kim, 31, who is frequently the centrepiece of the isolated country's propaganda, has not been photographed by state media since September 3, fuelling speculation he is unwell. He has also been seen walking with a limp

'The wealth and prosperity of our socialism is thanks to the painstaking efforts of our marshal, who keeps lighting the path for the people, like the flicker of a flame, despite suffering discomfort,' a voice over for the hour-long documentary said.

The documentary was followed by a pre-recorded broadcast of a North Korean Supreme People's Assembly meeting from which Kim Jong Un was notably absent.

Kim has rapidly gained weight since coming to power after his father died of a heart attack in 2011, photos released by state media show.

North Korea observers speculate Kim's weight and family background may have contributed to his condition.

Now and then: Kim has rapidly gained weight since coming to power (right) after his father died of a heart attack in 2011, photos released by state media show

'Disease of Kings': Historically known as 'the disease of kings', with Henry VIII a known sufferer, gout is a form of inflammatory arthritis which has long been thought to be caused by an overindulgent lifestyle

'Based on his gait, it appears he has gout - something (due to) diet and genetic predisposition that has affected other members of the Kim family,' said Michael Madden, an expert on the North Korean leadership and contributor to the 38 North website.

'DISEASE OF KINGS': WHAT IS GOUT? Historically known as 'the disease of kings', with Henry VIII a known sufferer, gout is a form of inflammatory arthritis which has long been thought to be caused by an overindulgent lifestyle. The condition used to be rare among young people, but research suggests it is becoming more common with the obese getting it a decade earlier than healthy weight people. Men are more likely to develop gout than women because their uric acid levels rise during puberty and remain higher than women through adulthood. It usually first appears between the ages of 30 to 60 and becomes more common with age. The condition is characterised by sudden onset of acute pain, redness and swelling in the joints such as the big toe. Gout is caused by a build-up of uric acid in the blood. Uric acid is a waste product that forms when the body breaks down chemicals in the cells known as purines. If you produce too much uric acid or excrete too little when you urinate, the uric acid will build up and may cause needle-like crystals in and around the joints, most commonly in the foot (particularly the big toe), but also the knees, fingers, forearms and elbows. The crystals may spill over from the joint cartilage into the joint space, causing a painful attack. Foods naturally high in purines include red meat – such as beef, lamb and pork - seafood, especially shellfish and oily fish, and offal. 'It is protein-rich foods that cause gout,' dietitian Helen Bond told MailOnline. 'Cheese is not a high risk food, although eating a lot of it will mean he is likely to have high calcium – and cholesterol – levels.' Other risk factors include obesity - partly because of extra pressure on the joints and chemical changes as a result of the fat - and heavy alcohol consumption, particularly beer, which is high in purines, and spirits. Smoking is not generally seen as a risk factor for gout. Advertisement

The 31-year-old North Korean leader got a taste for Swiss cheese while a student in Switzerland - and is understood to love it so much that he imports vast quantities, despite Western sanctions.

A unhealthy appetite for Emmental, also known as Swiss cheese, is believed to be a key factor in Kim's weight ballooning so much in recent months that he now walks with a limp.

Experts believe Kim may be deliberately gaining weight in order to look more like his grandfather Kim Il-sung, who is venerated in North Korea as the nation's founder and even now - exactly 20 years after his death - is still considered the head of state, with the title Eternal President of the Republic.

Kim has not been a presence in state media since attending a Pyongyang concert on September 3.

There's been no discussion of the absence in the authoritarian North's media.

North Korea's official Korean Central Television says the Supreme People's Assembly approved the promotion of Hwang Pyong So as the vice chairman of the country's powerful National Defense Commission.

Kim Jong-un's unhealthy obsession with Emmental has led to him importing vast quantities of the cheese for his own consumption - despite millions of North Koreans struggling to find enough to eat.

Malnutrition is widespread and famines often break out in the country, which is still reliant on foreign food aid as a result of economic mismanagement and the loss of Soviet support in the 1990s.

But despite the suffering of his 25 million citizens, Kim continues to gorge on Swiss cheese in such vast quantities that he is waistline is expanding at a dangerously rapid rate, according to the Mirror.

North Koreans who have managed to flee the country believe the weight gain may be deliberate in order to look more like his corpulent late grandfather Kim Il-sung.

He established an all-pervasive cult of personality around himself after turning North Korea into a oppressive single-party socialist state in the early 1980s.

Defector Cho Myung-Chul, of the Saenuri Party, said: 'North Koreans think being fat is good, unlike South Koreans who want to be skinny.