The US President appears to have lost an inch in height, meaning he narrowly keeps an overweight BMI, rather than being obese.

U.S. Republican presidential candidate Donald Trump eats a pork chop at the Iowa State Fair during a campaign stop in Des Moines, Iowa, United States, August 15, 2015
Image: The President has a well-documented love of fast food

Donald Trump's first medical exam since becoming US President was intended to silence those who doubted his mental ability.

Instead it has spawned a movement of people who believe Mr Trump may have fudged his height so he could avoid being assessed as obese.

Navy doctor Ronny Jackson, who administered the physical exam, reported that Mr Trump was 6' 3'' and 239 pounds (17 stone), which would give him a BMI of 29.8 - making him overweight.

But according to a copy of his driving license issued in May 2012 - published by Politico after an open records request - Mr Trump is 6' 2''.

President Trump
Video: Trump's cognitive ability is normal, says White House

It may only be an inch but it is the difference between an overweight BMI or an obese one, which according to the NHS is 30.6 and above.

Amid further questions over the President's weight, Guardians of the Galaxy filmmaker James Gunn is among a number of people who have demanded Mr Trump be weighed in public.

Offering to donate $100k (£72,470) to charity to make it happen, Gunn said he wanted Mr Trump to "step on an accurate scale with an impartial medical professional, okayed by both of us".

Others have compared famous sportsmen of the same weight and height as Mr Trump to lay doubt on the results of the physical exam.

Those behind the Twitter campaign are calling themselves "girthers" - a play on the "birther" movement revived by Mr Trump in 2011 when he alleged that his predecessor Barack Obama was born in Kenya and, therefore, was not eligible to be US President.

Mr Trump, who has not yet responded to the claims, would not be the first US President at the wrong end of the weight spectrum.

William Howard Taft famously weighed more than 350 pounds (25 stone).

According to the History Channel, Taft once commissioned a company to make the "largest solid porcelain tub ever made for an individual". A photo published in 1909 showed four average-sized men sitting comfortably inside it.

President Taft died at 72, just a year older than Mr Trump is now.

Among the healthier presidents, George W Bush used to make time for running or exercise every day, once telling Runner's World that he sometimes ran on Air Force One while travelling.

President Obama reportedly kept a strict morning workout routine of weights and cardio starting at 6.45am each day.

Barack Obama and Donald Trump
Image: Barack Obama and Donald Trump are both regularly spotted on the golf course

Mr Trump's exercise revolves around golf and he has a well-documented love of fast food.

According to Michael Wolff's "expose" Fire And Fury, the President even likes to eat cheeseburgers in bed.

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In December 2015, Mr Trump's personal physician said the billionaire was in a peak state of health.

Dr Harold Bornstein, who had looked after Mr Trump's health since 1980, wrote: "If elected, Mr Trump, I can state unequivocally, will be the healthiest individual ever elected to the presidency."

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