PUBLISHED: 20:37 EST, 13 March 2012 | UPDATED: 04:02 EST, 14 March 2012
Don’t choke on your bacon buttie, but in the medical profession’s relentless quest to find ever more things that may kill us, health officials are turning up the heat on red meat — again.
A major new study of 120,000 people has shown that reducing the amount of beef, pork and lamb in our diet to 1½oz a day could prevent one in ten early deaths in men, and one in 13 premature deaths in women.
The Harvard University findings are just the latest in a long line of studies suggesting that our love of juicy red meat is slowly killing us.
Some anti-cancer campaigners say the evidence is so damning we should avoid processed meat altogether. No crispy bacon for breakfast; no sausages on the barbecue; no ham sandwiches and no burgers topped with ketchup.
But other nutritionists say the risks are exaggerated and that cutting out red meat from our diets could do more harm than good.
So who’s right? And what is the confused cook supposed to eat?
The latest research found that eating one extra portion of steak, lamb or pork every day — about the size of a pack of cards — increased a person’s risk of dying from heart disease by 16 per cent, and raised their chance of developing a fatal cancer by 13 per cent.
Processed meats — such as hams, sausages and burgers — were more deadly. Adding two rashers of bacon or a sausage to breakfast increased the chance of premature death by 20 per cent. But how much red meat should we be eating?
The Department of Health recommends we all have no more than 2½oz (70g) of red meat a day. For example, that would be three sausages on a Monday, three slices of lamb on Tuesday, a quarter-pounder on Wednesday, a small steak on Thursday and fish or poultry over the next three days. But the Harvard authors say even that is too much.
This anti-bacon backlash will have surprised many meat lovers. After all, human beings have been happily devouring red meat for millennia.
Marks found on fossilised animal bones in Ethiopia show that one of our ancestors — the ape-like Australopithecus afaransis — was butchering antelope and cattle 3.4 million years ago.
Meat is a rich source of fat and protein, and many anthropologists believe mankind needed to switch to meat-eating to give us the nutrition essential to evolve bigger, smarter brains.
However, we shouldn’t follow the example of our ancestors too closely.
For much of human history, most people would have died from infectious disease, childbirth, injuries or malnutrition long before they had to worry about cancer and heart disease — illnesses of middle and old age. So our forebears could have eaten slabs of bison to their hearts’ content — something else would have killed them by the age of 30.
So what is it in red meat — and particularly processed meat — that is so harmful? The evidence is far from conclusive.
All types of red meat, whether processed or unprocessed, contain a form of iron called haem — the pigment that gives red meat its colour. Iron is an essential nutrient.
However, haem can also trigger the formation of a class of harmful chemicals called ‘nitroso compounds’ (NOCs) in the body and some types of these chemicals have been linked to bowel cancer.
Barbecued or chargrilled meat is thought to be particularly bad for us. For, when meat is charred, compounds called Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) are formed. Again these are thought to increase the risk of bowel cancer.
The worst type of meat is that which has been cooked and processed. These contain cancer-causing haem, HCAs and PAHs as well as preservatives called nitrates and nitrites, which also increase the risk of bowl cancer. However, the links between red meats and heart disease are less clear.
Some nutritionists believe the high doses of salt in processed food may be to blame. Professor Frank Hu of Harvard School of Public Health in Boston, author of the new research, blames the saturated fats in all red meat for clogging up arteries.
But not all nutritionists are convinced. Many believe the benefits of red meat are too often overlooked.
Laura Wyness, of the British Nutrition Foundation, says: ‘The evidence for an association between red meat consumption and risk of cardiovascular disease is inconclusive.
‘Although red meat contains saturated fat, it also provides nutrients that can protect against cardiovascular disease such as omega 3 fatty acids, unsaturated fats, B vitamins and selenium.’
In fact, red meat contains many nutrients such as selenium and vitamins D, B3 and B12.
Wyness warns that some of these are already in worryingly short supply in the diets of some sections of the population. Too little iron in the diet causes anaemia while zinc is essential for growth in childhood and fighting off infections.
Richard Young, of the Soil Association, believes British consumers should be careful when drawing conclusions from U.S. studies.
‘Not all red meat is the same,’ he said. ‘In America, most cattle are fed large amounts of grain. In Britain, the majority are fed on grass and that makes a big difference to the quality of the meat.”
In studies, grass-fed cattle have been shown to have higher levels of beneficial omega 3 fatty acids compared to grain-fed livestock — nutrients that can protect against heart disease.
The most recent data suggest that in Britain, most of us meet the guidelines laid out by the Department of Health. Men consume an average 2½oz (70g) of red meat each day while women eat 2oz (52g). However, a third of the population are still red meat gluttons, devouring more than 3½oz or 100g a day.
Jessica Harris, health information manager at Cancer Research UK, said the risks should be put in context.
‘The risks of smoking massively outweigh these risks,’ she said. ‘Red meat isn’t as important as being overweight or drinking alcohol. But that’s not to say it isn’t making a significant contribution.
‘Eating less red meat and processed meat doesn’t guarantee that you don’t get cancer, but it makes sense to control the things we can control.
‘We don’t want to be kill-joys and eating meat a few times a week isn’t likely to cause any great problems. But if people are having lots of processed meat and red meat every day, they should think twice.’
As the anti-red meat movement grows stronger, carnivores will inevitably feel their lifestyles are under threat. The Department of Health is under pressure to reduce its recommended red meat intake even further. But for some health campaigners, that won’t be enough.
How long before health campaigners lobby for laws which would ban children from burger bars, or before workplace canteens are ‘encouraged’ to phase out traditional breakfast fry-ups?
Smokers have already been forced out on to the streets. How soon before they are joined on the pavement by office workers clutching illicit bacon butties?