It has led to persistent rumours about the North Korean leader's health. But what's the reason behind his dramatic weight loss? As Kim Jong-un turns 38 today, Express.co.uk provides an insight into questions around his health.

       Kim Jong-un has been the autocratic ruler of North Korea since taking the reins from his father in 2012.

       He became leader at just 27 years old, but very little was known about him.

       Mr Kim's rule has been carefully curated with state media largely controlling his image.

       This makes it very difficult to see past the propaganda, but there have been a few signs this year that have led to speculation suggesting the dictator might not be in the best of health.

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       Kim Jong-un’s recent public absences

       In April 2020, US officials said they were unsure of Kim Jong Un’s health, as reports suggested he had undergone cardiovascular surgery.

       When he returned to public duties after about three weeks, some onlookers noticed a mark on his arm - and speculated he could have undergone surgery.

       Mr Kim is known to be a heavy smoker and has been overweight for a long time.

       But there are signs that, as Mr Kim draws closer to his forties, he is starting to focus more on his health.

       Since his absence in 2020, he seems to have lost around 20 kg (44 pounds), appearing noticeably leaner in June 2021.

       However, Mr Kim has been absent from several public appearances this year, the most notable of which took place between September and November 2021.

       The dictator was absent for over a month, which is his longest absence in seven years.

       Reports by the NK News revealed that satellite images showed an increase in activity around his east coast beach house and a lakeside mansion in Pyongyang.

       These locations are reportedly where the dictator retreats to during periods of illness.

       State-controlled North Korean media didn’t update their citizens on their leader’s health during his absence from October 12 to early November 2021.

       When he eventually returned state officials didn’t provide a reason for his prolonged absence.

       The return was marked with an undated photo of Mr Kim inspecting a construction site in Samjiyon city.

       The photo was provided by the North Korean government on November 16, which suggests that he had returned to public duties by then.

       In 2021, Mr Kim had eight breaks from public engagements spanning at least 14 days, according to the Independent.

       As North Korea is a famously closed-off country, onlookers take great interest in Mr Kim’s public appearances to look for clues surrounding the state of his leadership.