Why you should never order a steak well done

People who ate more processed and red meat were 47 per cent more likely to have liver disease. Photo / Getty Images

Eating red meat can boost the risk of developing deadly liver disease, a study suggests.

Israeli scientists have found the risk of non-alcoholic fatty liver disease is highest for those who enjoy their steak 'well done'.

The disease, referred to as 'human foie gras', can lead to cirrhosis, which can in turn trigger liver cancer or cause the organ to fail.

Evidence already links consumption of meat to cancer, heart disease and diabetes - but scientific trials are scarce on its links to NAFLD.

The new study, which also confirmed eating red meat leads to a higher risk of diabetes, shines a light on the possible cause of the chronic liver disease.

Some 789 adults were quizzed about their eating and cooking habits. They also underwent liver ultrasound scans and tests for insulin resistance.

People who ate more processed and red meat were 47 per cent more likely to have liver disease, the University of Haifa experts found.

While they were 55 per cent more likely to have insulin resistance, the researchers reported in the Journal of Hepatology.

Cooking meat at high temperatures for longer periods of time, or until it's well done, was also associated with a higher risk of both.

This was in comparison to those who preferred to eat more 'rare' meat, or cooked for less time, the researchers noted.

Lead author Shira Zelber-Sagi said: "Evidence is mounting with regard to the harmful effect of over-consumption of red and processed meat."

"In order to prevent insulin resistance and NAFLD, [people should consider] choosing fish, turkey or chicken as an animal protein source.

"In addition, steaming or boiling food [is better than] grilling or frying meat at a high temperature until it is very well done."

Preparing meat 'well done' forms compounds known as heterocyclic amines (HCAs) that are tied to both liver disease and insulin resistance.

The perfect steak should be cooked and eaten at a medium-rare level. Photo / Getty Images

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in developed countries, affecting up to one in four adults.

It occurs when fat accumulates within the liver cells in people who do not consume excessive alcohol and is commonly associated with obesity and diabetes.

If left untreated, it can lead to cirrhosis, which can lead to liver failure and cancer of the vital organ. Both of which can be deadly.

Both NAFLD and insulin resistance are among the suite of symptoms and traits that make up so-called metabolic syndrome.

The medical community has warned that the findings mean adults should limit how much red and processed meat they eat.

Dr Jeffrey Schwimmer, director of the Fatty Liver Clinic at Rady Children's Hospital in San Diego, called for red meat to be eaten just once a week.

"There is not a need for red meat, so one could choose to avoid it all together," said Dr Schwimmer, who wasn't involved in the study.

"For those that do eat meat, it would be reasonable to limit red meat to once a week and to limit processed meat to occasional use only."

The study follows a Leeds University trial earlier this month that revealed cutting out red meat significantly cuts the risk of developing bowel cancer.

WHAT IS NON-ALCOHOLIC FATTY LIVER DISEASE?

Despite its name, non-alcoholic fatty liver disease isn't solely caused by eating too much fat.

Instead, it is fed by over-eating in general, with some of the excess calories being stored as fat in the liver.

Doctors say that up to a third of Britons have non-alcoholic fatty liver disease, in which the liver becomes clogged with fat.

It is often referred to as 'human foie gras', as it occurs in much the same way as a goose liver is fattened for foie gras production.