Sausages, ham, bacon and other processed meats appear to increase the risk of dying young, a study of half a million people across Europe suggests.

It concluded diets high in processed meats were linked to cardiovascular disease, cancer and early deaths.
The researchers, writing in the journal BMC Medicine, said salt and chemicals used to preserve the meat may damage health.
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It showed people who ate a lot of processed meat were also more likely to smoke, be obese and have other behaviours known to damage health.

However, the researchers said even after those risk factors were accounted for, processed meat still damaged health.
One in every 17 people followed in the study died. However, those eating more than 160g of processed meat a day - roughly two sausages and a slice of bacon - were 44% more likely to die over a typical follow-up time of 12.7 years than those eating about 20g.
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"Something has been done to it to extend its shelf life, or to change its taste, or to make it more palatable in some way... and this could be a traditional process like curing or salting."

She said even good quality ham or sausages were still classed as processed meat, while homemade burgers using fresh meat were not.

Processed meats - such as bacon, sausages and ham - do cause cancer, according to the World Health Organization (WHO).

Its report said 50g of processed meat a day - less than two slices of bacon - increased the chance of developing colorectal cancer by 18%.

Processed meat includes bacon, sausages, hot dogs, salami, corned beef, beef jerky and ham as well as canned meat and meat-based sauces.

"For an individual, the risk of developing colorectal (bowel) cancer because of their consumption of processed meat remains small, but this risk increases with the amount of meat consumed," Dr Kurt Straif from the WHO said.

The survey looked specifically at asthma symptoms - breathlessness, wheeze, chest tightness - and intake of cured meat: a single portion was two slices of ham, one sausage or two slices of salami.

Among the people with asthma, higher meat consumption was linked with a worsening of their lung symptoms.
People who said they consumed more than four portions a week - eight slices of ham or four sausages, for example - had the biggest deterioration of their asthma by the end of the study.

The experts stress that their work cannot prove diet is definitely to blame. There are lots of factors in a person's life that can make their asthma worse.

The researchers tried to eliminate the most obvious ones, controlling for things like obesity, and the link between processed meat and worsening asthma remained.