Monday, April 02, 2012

Bacon can be good for you

Some cautious backpedalling below

The Saturday morning staple of a bacon or sausage sandwich has received a bashing of late. In January, researchers from Sweden claimed that eating just 50g (1.7oz) of processed meat a day – the equivalent of one sausage or two rashers of bacon – raises the risk of pancreatic cancer by a fifth.

And another study claimed that a diet high in these processed meats may also lead to bowel cancer and heart disease.

But, as nutritional experts attest, pork is the most unfairly maligned of meats and a few good-quality rashers or bangers could do us good, if eaten in moderation.

‘Pork has a bad reputation, mainly because it’s associated with cheap processed sausages, whose contents are largely unknown, or fatty bits of bacon and flavourings. But that reputation should not apply to products from outdoor-reared, well-nourished animals,’ says Kumud Gandhi, a food scientist and founder of The Cooking Academy.

Catherine Collins, principal dietician at St George’s Hospital London, says: ‘Bacon, sausages and other processed pork products have sodium nitrite added as a preservative and flavour-enhancer, giving them their salty flavour.

‘But this chemical can form a carcinogenic substance called nitrosamine in the digestive system, which may be the reason the Swedish study found a small cancer risk, although it’s far from conclusive.

‘The people in the Swedish study wouldn’t have just been eating a  sausage once a day – they will have been eating a whole fry-up. Someone with this kind of lifestyle may well be obese or smoke, which are big known risk factors for pancreatic cancer,’ says Collins.

‘There is no evidence that eating processed meats once or twice a week as part of a balanced diet will  do any harm whatsoever.’

Department of Health guidelines  suggest that  red-meat consumption of more than 70g (2½ oz) per day, the equivalent of two portions a week, may raise the risk of bowel cancer.

Collins says: ‘As a red meat, pork contains haem iron, which is thought to be potentially carcinogenic. Two portions a week – bacon with eggs, or a meal with sausages – has not been found to pose any risk. Studies have also shown that if you blacken any meat, the charred substance could be cancer-causing, but if you eat ‘barbecued’ sausages with yogurt, the bacteria it contains renders these carcinogens less harmful.’

Nutritionally, pork ranks highly among meats. It is rich in essential vitamins and minerals, including B6, B12, niacin, thiamine, riboflavin, iron, magnesium, potassium and zinc, and it’s high in protein, contains carbohydrates and a lean cut is low in fat and calories.

Nutritionist Zoe Harcombe says: ‘Typically, about 45 per cent of the fat in pork is unsaturated. Most of that is oleic acid, the same healthy fat found in olive oil, which is known to help lower cholesterol levels.  ‘Of course, the rest is unhealthy saturated fat, so moderation is key.’

If you don’t eat fish or nuts, pork is a useful alternative source of omega 3 fatty acids, says Gandhi. ‘A piece of loin pork, the size of a deck of cards (100g, 3½oz), will give half your daily protein intake and 15 per cent of your daily iron intake. Protein is important for children, so if you give them two good-quality  sausages made from outdoor-reared, toxin-free pork and which contain  90 per cent pork meat, that’s a good, nutritious meal.’

Pork is also a source of zinc and  Vitamin D. ‘If you are worried about nitrites, choose a sausage with a higher meat content – more than 80 per cent – or a brand of bacon without added water, as these will need fewer flavour enhancers,’ says dietician Anna Raymond.

Rachel Green, of BBC3’s Kill It, Cook It, Eat It, says: ‘Buy free-range  pork sausages from butchers or farm shops. I like to use more mature, flavoursome rare-breed porks such as Gloucestershire Old Spot or Tamworth. With bacon, look for British dry-cured for the healthiest cuts.’

Knowing where your meat comes from and what has been done to it is key to its quality and nutritional value. Michael Jones, owner  of Drings butchers in Greenwich,  London, says: ‘If you get a good piece of bacon, which hasn’t been cloaked in sugar and fat, it’s just a good piece of meat that is tasty, nutritious and ethical too.’


Vaccine to stop heart attacks could be developed

This sounds a bit far-fetched but time will tell.  The approaches outlined below also give some concerns about possibly serious side effects

Vaccines against heart disease could be available within five years, a London conference has heard.

Injections of antibodies could prevent the build up of fat in the arteries which cause narrowings and break off leading to heart attacks, experts said.

It would be the first time that the underlying causes of heart disease was targeted instead of reducing factors such as high levels of bad cholesterol and blood pressure which increase the likelihood of heart disease developing.

Several different approaches are in the pipeline and could be licensed within five years, the Frontiers in CardioVascular Biology meeting at Imperial College London was told.

Independent experts said the vaccines were 'very promising' and could have a big impact on the treatment of the disease.

Cardiovascular disease causes one in three of all deaths in Britain accounting for 191,000 deaths a year.

There are around 2.7m people with heart disease and treatment costs £3.2bn a year.

Lack of exercise, poor diet, smoking and drinking too much alcohol are the main causes of heart disease but it is also known that there are strong hereditary factors too.

Coronary heart disease occurs when fatty plaques build up in the blood vessels feeding the heart and over time become narrowed. Parts of the plaque, known as atheroma, may break off causing a clot to form which can block the artery causing a heart attack.

Prof Nilsson, who is professor of experimental cardiovascular research at Lund University, in Sweden told the conference: “People at high risk of heart attacks are likely to be the first candidates for immune approaches. Such treatments, since they’ve totally different modes of action, could be used in addition to the current therapies."

Prof Nilsson said that although current treatments including statins and blood pressure drugs are very effective and reduce the risk of cardiovascular problems such as heart attacks and strokes by around 40 per cent, 'it should not be forgotten that 60 per cent of cardiovascular events continue to occur'.

Prof Nilsson told the conference that experiments had shown it was possible to alter the way the immune system reacted to plaques in the arteries to reduce inflammation and the severity of the build up.

Working with Prof Prediman Shah, from Cedars-Sinai Heart Institute in Los Angeles, the team were able to formulate a vaccine that reduced plaque build up by 60 to 70 per cent in mice.

The resulting CVX-210 vaccine, currently in development as an injection by CardioVax, is waiting regulatory clearance to start clinical trials.

A second vaccine using the same materials has been formulated as a nasal spray, Prof Nilsson said.

Another approach, of directly injecting antibodies against bad low density lipoprotein which carries cholesterol in the blood and forms the basis of the plaque, is already in trials.

Prof Nilsson said: “The rationale is that since oxidised LDL plays a major role in the development of atherosclerotic plaques and harmful inflammatory processes, directly targeting oxidised LDL should prevent plaque formation and reduce inflammation."

Early studies have shown that the antibody, called BI-204, developed jointly by BioInvent and Genentech, reduced plaques by half and was well tolerated when tested in 80 healthy people.

A trial of BI-204 in 144 people with heart disease is underway in America and Canada where body scans will measure plaques in the arteries over time.

Prof Nilsson said it was unlikely that the products would be given as traditional vaccines in early childhood and instead were more like drugs in that they would need to be given repeatedly.

He said: “Both these treatments are far more like drugs – to be effective they’d need to be given long term. The antibody therapy in particularly is likely to be expensive so you could probably only afford to give it to high risk populations rather than everyone."

Professor Peter Weissberg, Medical Director at the British Heart Foundation said: “A vaccination approach to the treatment of atherosclerosis is based on an attempt to interfere with the cellular mechanisms that cause life threatening build up of fatty deposits.

“There will be great interest in the outcome of the on-going studies to see firstly if this approach is safe and secondly, whether it can influence the progression of vascular disease in the long term.

“It is very promising, but it will take some time before we know if it is successful and, if so, which patients are likely to benefit most from this treatment.”


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