Research from The Royal Veterinary College (RVC), published in the Canine Medicine and Genetics journal, has found that the pets are significantly more likely to suffer from disorders affecting the airways and the eyes.
Pugs are one of the most popular dog breeds in the UK, known for their big eyes and small squashed-looking faces.
Experts are advising the public against buying the dogs until there is an improvement in their health and their body shape shifts to being less extreme.
The study compared the health records of 4,308 pugs with 21,835 non-pug dogs.
It found that pugs are around 1.9 times more likely to suffer from one or more disorders compared to other dogs, indicating a poor overall health status among the breed.
Of the 40 most common disorders affecting all dogs, pugs had a higher risk of 23 out of the 40 (57.5 per cent) disorders compared with a lower risk of only seven out of 40 (17.5 per cent) disorders.
Pugs had the highest risk of brachycephalic obstructive airway syndrome (BOAS) with the breed almost 54 times more likely to have the condition.
BOAS refers to a range of respiratory problems experienced by flat-faced dogs, due to their short noses and the shape of their faces.
Pugs are also at increased risk of having narrowed nostrils, skinfold infections and obesity. Obesity affected 17.4 per cent of pugs, and 6.9 per cent of other dogs.
Experts said this results in “severe welfare consequences for affected dogs, including shortened life span, reduced quality of life and increased risk for osteoarthritis, diabetes mellitus and neoplasia”.
However, the study found pugs did have reduced risk of some conditions, including heart murmurs, aggression and wounds.
“Highly differing heath profiles between pugs and other dogs in the UK suggest that the pug has diverged substantially from mainstream dog breeds and can no longer be considered as a typical dog from a health perspective,” the study said.
Dr Dan O’Neill, associate professor in companion animal epidemiology at the RVC and lead author of the paper, commented: “Although hugely popular as pets, we now know that several severe health issues are linked to the extreme body shape of pugs that many humans find so cute.
“It is time now that we focus on the health of the dog rather than the whims of the owner when we are choosing what type of dog to own.”
While there was a five five-fold increase in Kennel Club registrations of pugs between 2005 and 2017, there is a growing concern over the health of flat faced dogs.
Norway banned the breeding of flat-faced dogs earlier this year, with an Oslo court ruling that the practice is cruel and results in man-made health problems, and is in violation of Norway’s Animal Welfare Act.
Justine Shotton, British Veterinary Association president, said: “This study clearly demonstrates how it is the extreme characteristics many owners find so appealing, such as squashed faces, big eyes and curly tails, which are seriously compromising pugs’ health and welfare and often result in a lifetime of suffering.
“While these extreme, unhealthy characteristics remain, we will continue to strongly recommend potential owners do not buy brachycephalic breeds such as pugs.”