Crematoria are struggling to deal with spiralling rates of obesity.
Some coffins are twice as wide as the standard size
Expanding waistlines are forcing many councils to spend thousands widening their furnaces, the Local Government Association has warned.
In some cases grieving relatives have to travel hundreds of miles to find crematoria that can accommodate over-sized coffins.
Standard coffins range from 16-20 inches, but coffins up to 40 inches are becoming increasingly common.
The LGA, which represents over 400 councils in England and Wales, is warning that local authorities are finding that many of their furnaces are too narrow to deal with these larger coffins.
Around 430,000 cremations take place in Britain each year.
In Lanarkshire, Scotland, a new 41-inch-wide cremator, has been dealing with the funerals of obese people from all over Scotland.
And Lewisham Council has ordered a special cremator from America, measuring 44 inches in width.
The crematorium has taken coffins from as far away as the West Midlands and Gloucester.
As part of a £1.2m refurbishment, a new furnace at Mintlyn Crematorium in Bawsey was recently installed by King's Lynn and West Norfolk Council to accommodate coffins a metre wide.
Blackburn with Darwen Council has plans to install a 42-inch cremator in the next few years to deal with wider coffins.
In 1980, 8% of women and 6% of men were classified as obese.
By 2004 this had increased to 24% of men and women and by 2010 is expected to rise to a third of all adults.
Hazel Harding from the LGA, said: "As long as the nation keeps on piling on the pounds, pressure will continue to be placed on crematoria.
"This is just another demonstration of how the UK's obesity problem is putting a real strain on public services."
"The death of a loved one is always a difficult time and having to decamp to another area for the cremation just adds to the ordeal.
"It is important that grieving relatives get the service they deserve and councils are doing what they can to accommodate larger clients locally."
Tim Morris, chief executive of the Institute of Cemetery and Crematorium Management said: "The Institute has received calls from funeral directors from all parts of the country whose local crematorium is unable to cremate large coffins.
"The likelihood is that a large number of facilities will be upgraded to meet these requirements with some taking this opportunity to install a larger cremator."
Dr David Haslam, clinical director of the National Obesity Forum said: "It brings it home how big a problem it is.
"We've heard of obese people having to use animal MRI scanners and problems with aeroplane seats but this is linking it with death and of course there is an increased risk of premature death with obesity."
But Dominic Maguire, funeral director in Glasgow and spokesperson for the National Association of Funeral Directors said it wasn't a common problem.
"All crematoria can accomodate the overwhelming majority of coffins that are brought to them and only very rarely would a situation arise where there would be a requirement for an outsize crematorium."