Nutrition

Processed foods, such as ham, bacon and sausages, are bad news for our health, but what about salt-cured or pickled meat?

Aresalt-cured and pickled meats bad for our health?

Question:

Are pickled pork and corned silverside as bad for our health as processed ham, pork luncheon, bacon and sausages?

Answer:

You could say it’s been an annus horribilis or two for the processed-meat industry. In late 2015, the International Agency for Research on Cancer (IARC) reclassified processed meat as “carcinogenic to humans”. More recently, listeria was discovered in New Zealand-sourced processed meats. So, where do pickled pork and corned silverside fit in? IARC defines processed meat as “hot dogs [frankfurters], ham, sausages, corned beef and biltong or beef jerky, as well as canned meat and meat-based preparations and sauces”. So, pickled pork and corned silverside are classed as processed meat.

The agency concluded that eating 50g of processed meat a day increases the risk of colorectal cancer by 18%. It is also linked to an increased risk of cardiovascular disease and type 2 diabetes, say University of Otago health economists Cristina Cleghorn and Nick Smith, in a review for the New Zealand Medical Journal.

But are pickled pork and corned silverside better or worse than sausages and bacon?

IARC’s official line is that there isn’t enough research data available to be able to differentiate risk based on the type of processed meat eaten or the cooking method used.

However, Smith says evidence favours a move from processed red meats to processed white meats, such as canned chicken. He points to the results of a large population study published in the British Medical Journal in May. Involving more than 530,000 participants tracked over 16 years, the BMJ study found a higher risk of mortality was linked to processed meat and red meat.

But the risks were reduced if meat was replaced with any white meat, particularly unprocessed white meat.

The BMJ study findings suggest that the haem iron levels matter, says Smith. Red meat has higher haem iron levels than white meat. What’s more, “products like blood sausage are probably going to be a higher risk than processed meat with lower residual blood products”.

Evidence also suggests avoiding smoked meats and very salty meats, says Smith, although he notes some smoking methods can reduce levels of suspected toxicants.

Corned beef and pickled pork are both high-salt meats. A 100g serving of corned beef has about 1300mg of sodium, significantly more than the 30-50mg found in 100g of beef steak.

In more bad news for the processedmeat industry, a microbiological survey of packaged ready-to-eat red meats in New Zealand retail stores found unacceptable levels of Listeria monocytogenes in 6.4% of samples.

The failed products originated from eight of the 33 producers tested, the researchers said in a report in last month’s Journal of

Food Protection. Corned beef and roast pork were among failed products with listeria levels above food-safety regulation requirements.

Listeria monocytogenes is harmful to humans and can lead to either non-invasive or invasive listeriosis. Symptoms include fever, headache, diarrhoea and vomiting. In more serious cases, it can lead to meningitis and blood poisoning. Listeriosis can be devastating for pregnant women. Although symptoms may appear mild in an expectant mother, the disease can result in premature birth, miscarriage or stillbirth. The consequences for people with low immunity can also be serious.

Cooking foods thoroughly does destroy listeria, but as these meat products were “ready to eat”, consumers would more than likely eat them without further cooking.

“There probably need to be warning labels required around the possible risk of contamination with listeria so that consumers can make informed decisions,” says Smith. He believes the food industry needs to improve its quality control to prevent contamination occurring again. He points to the marked decline in campylobacteriosis cases after the Government required food industry changes.

The best way to lower our health risk is to switch to a largely plantbased diet, with unprocessed meat used as more of a side dish.

A 100g serving of corned beef has about 1300mg of sodium, significantly more than the 30-50mg found in 100g of beef steak.