Positive Health Online

Since the 1970s, red meat has been suspected of increasing the risk of cancer. Recently the World Cancer Research Fund published its monumental review of the evidence on nutrition, food and cancer.

They confirmed that eating large amounts of red meat increases the risk of several cancers, probably colorectal cancer and possibly pancreatic, breast, prostate and kidney cancers. They recommend eating less than 80g (3 ounces) of red meat (beef, lamb or pork) a day. They advise people to eat fish, poultry or meat from wild animals instead but preferably to have a diet based primarily on plant-foods.

The evidence comes from studies of meat from intensively raised domesticated animals. Instead of cutting the amount of red meat you eat, would you be better off eating red meat from organically reared animals instead?

The principles and practices by which livestock are managed in a certified organic system are different than those in an intensive system. In an organic system, animal husbandry is based on the physiological and behavioural needs of the animals. Animals are not caged, tethered or confined in buildings without adequate natural ventilation and lighting. They are given enough room for free movement and kept in appropriate size herds and flocks. Attention is given to bedding materials, paints and wood preservatives used for housing, and access to pasture and fresh water. The health and vitality of the animals is maintained by sound nutrition and good management practice. Prophylactic antibiotics should not be necessary. All growth promoters and hormones are prohibited. Veterinary drugs are allowed only where there are no effective complementary treatments. Withdrawal periods after giving a veterinary drug are strict in order to prevent residues in meat.

The question is whether organic animal husbandry makes the meat substantially different than meat from intensively reared animals.

There are a few ways the meat could differ enough to account for a lower risk of cancer. There could be differences in the amount or kind of fat or in the amount of contamination by growth hormones.

Is there a difference in fat content? Intensive methods of livestock production have resulted in meat with a high fat content. Wild cattle contains more than three times as much protein as fat compared to domestic cattle who have half as much protein as fat. As well as increasing the total fat content, intensive feeding changes the ratio of polyunsaturated to saturated fatty acids. In domestic animals, the ratio is 1 to 50. In wild animals, it is 1 to 2.3.

There is strong though not totally convincing evidence that total fat and saturated fat increase the risk of colorectal and prostate cancers. There may well be a link with breast cancer. Meat and dairy products are the main sources of fat and saturated fat in the British diet.

But is organic meat more like intensively grown meat or more like meat from wild animals? There are some comparative studies on the quality of meat from animals reared in organic and intensive farming systems but no conclusions about fat content can be drawn from them. We don't know how much total fat and how much saturated fat organic red meat has compared to conventional and wild meat. Is there a difference in contamination by growth hormones? Growth hormones are given to animals so that nutrients are more efficiently absorbed from the feed and converted into muscle rather than fat. Where used, they are administered in implants around the ear or as a feed additive. There are three kinds:

1 Natural steroid hormones – oestradiol, progesterone, testosterone,

2 Synthetic steroid hormones – Trenbolone, Finkplix, Ralgro, Stilbenes including DES (diethylstilboestrol).

3 Phyto-oestrogens derived from plants – Zeranol.

High levels of natural steroid hormones are carcinogenic, acting as promoters rather than as initiators of cancer. DES, one of the synthetic hormones, is carcinogenic in both experimental animals and in people who have taken it as a drug to prevent miscarriage.

Yet a 1995 scientific conference in the EU on the safety of growth hormones, the World Health Organisation and the World Cancer Research Fund have all concluded that there is no evidence of a health risk to people from either natural or synthetic growth hormones.

This conclusion is based on the low level of exposure to growth hormones in meat. Meat from intensively raised animals should not contain high levels as they are banned in the EU and in imports to EU countries. However, they are permitted in the USA. DES was banned for use as a growth promoter in animals in the early 1980s in all countries, including the USA.

Meat produced according to regulation in the EU or even in the USA poses no detectable risk to consumers. The potential risk is from illegal, past or improper use. Before the EU ban, growth hormones were used in the UK and exposure may have been higher than now. But compared to the levels of natural oestrogen in women who are not pregnant, the amount in American beef from oestradiol-treated steers is hundreds of thousands of times less.

DES was used from the 1950s until the early 1980s. Exposure to trace amounts of DES in food was substantially below levels found in women who had taken DES as a drug. One estimate was that the daily dose of DES from eating 100g beef containing 0.5 parts per billion DES was 10,000 times less than the DES dose received from drug treatment.

Both imported and home-produced meat is monitored for banned growth hormones by the Veterinary Medicines Directorate. In the latest reports of the surveillance scheme, there were no samples with levels above the action level.

In terms of the risk from growth hormones, there is no obvious advantage in buying organic meat.

If health is the only basis for decision making, I would keep the amount of red meat you eat down to less than 80g a day. That way you can afford to buy a small amount of the more expensive organic meat, knowing that the animals have been well looked after.