14 March 2011

4 minute read

A few individual studies have also found a link with prostate and pancreatic cancer.

The Soil Association says that widely-accepted concerns that the saturated fats found in red meat increase the risk of heart disease have found their way into the Government’s healthy eating guidelines.

There has also been research in Spain linking high red meat consumption to low male fertility.

However, it says that none of these negative effects has been established for chicken and other intensively produced white meat, so far.

One rather bizarre aspect of this issue, which has received little consideration, the Soil Association says, is that weekly consumption of beef in the UK fell from 244 grams per person in the early 1950s to 126 grams in the 1990s.

In contrast, chicken consumption during the same period increased from 19 to 237 grams and has risen further since.

Yet this is the very period during which cancer and heart disease has increased dramatically, the briefing note says.

This period equates to the major phase of agricultural intensification, when virtually all chickens and a significant proportion of cattle, even in the UK, were brought indoors and fed on a predominately cereal-based diet to increase productivity.

The organic food group points to research by scientists at the Institute of Brain Chemistry and Human Nutrition in London that has recently highlighted the fact that more than half the energy in a modern broiler chicken (as well as some organic chickens) comes from fat, whereas 60 years ago, the vast majority of the energy came from protein.

Even more significantly though, the Soil Association says, the proportion of the omega-3 fatty acid, DHA, found at significant levels in grass, has fallen dramatically in chicken meat, which today contains only one-fifth of the level found in wild birds.

In contrast levels of the omega-6 fatty acids derived from grain have not fallen, giving a highly unhealthy balance of almost ten times as much omega-6 as omega-3.

The scientists study associates this with the rise of brain dementia.

Professor Michael Crawford, one of the authors, says that ‘Essential fats for the brain are the priority…In biochemical terms the limiting factor for the brain is the omega 3 docosahexaenoic acid [DHA]… to get the same amount of DHA from a modern broiler chicken you need to eat about three to five chickens at a cost of over £12 and with 5,000 calories of thrombogenic and atherogenic fats included.’ (Crawford, 2009, pers comm).

While a similar trend has occurred with intensively-produced beef and pork, grass-fed beef has an omega 6 to omega-3 ration of just 1.65:1.

A very high proportion of beef in recent decades, however, has been produced intensively, in feedlots in the US and many other countries, and in the barley-beef systems pushed by MAFF for so many years.

The Soil Association asks, could this be an explanation for the studies that have found harmful trends associated with high red meat consumption?

"We have to remember too that the WCRF included pork in their definition of red meat and worldwide a high proportion of pork is produced in the most appallingly intensive conditions," the Soil Association says.

The beneficial effects of omega-3 fatty acids are, as yet, widely accepted only in relation to cardiovascular disease and it is for this reason that we are advised to eat two portions of oily fish a week, but recent research has shown that Western diets are typically as high as 16:1, omega-6 to omega-3, but that reducing this to:

• 2.5:1 reduced colorectal cancer cells and the risk of breast cancer in women,
• 5:1 suppressed inflammation in patients with rheumatoid arthritis. (Simopoulos, 2008)21.

Even the WCRF, which has been at the forefront of the global campaign to reduce the consumption of red meat, has acknowledged that the meat of wild animals has a very different fat profile to that of most farmed animals and may therefore not be linked to increased cancer risk, the association's briefing says.

"However, it has failed to acknowledge that production systems much closer to the wild are likely to produce meat with similar characteristics to wild animals.

"This is a serious omission, because in the absence of such a recognition economics are driving extensive producers out of business at a much faster rate than intensive ones.

"Meat and milk from predominantly grass-fed animals have other advantages too: higher levels of beneficial conjugated linoleic acid and many other important micro-nutrients associated with increased well-being," the Soil Association concludes.