by Catherine Haug (Jan 22, 2011)
The World Cancer Research Fund (WCRF) recently published their Expert Report Recommendations (1), based on the findings of the WCRF/AICRreport, Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective (2007). This was a review of over 7,000 independent studies on diet and cancer. Amongst the recommendations is a caution to avoid processed meats:
“There is strong evidence that … processed meats are causes of bowel cancer, and that there is no amount of processed meat that can be confidently shown not to increase risk …
Try to avoid processed meats such as bacon, ham, salami, corned beef and some sausages.”
They find processed meats especially troubling because they contain nitrates & nitrites, which are converted to cancer-causing nitrosamines when heated, especially from the high heat of grilling and broiling. Nitrates occur naturally at low levels in meats smoked or salt-cured at home; they occur at much higher levels in commercially processed meats because nitrates are added as preservatives. High-heat cooking of processed meats also produce heterocyclic amines (HCAs) which are also linked to cancer.
Yet many in our community rely on salt cures and smoking of meats as a way of preserving the bounty from fishing in the summer and hunting in the fall, for the remainder of the year. Indeed, ESP even has hosted presentations and published articles on how to do this kind of preservation:
- Gathering Summary: Canning & Dehydrating Foods
- Gathering Summary: Putting Food By, July 22, 2009
- The EssentiaList: Pickling & Lacto-Fermentation Introduction, Sources, & Recipes
- Handouts: Putting Food By
- Corning Beef (Salt Brine)
- Sugar and Salt in Food Preservation
What is one to do?
Should all smoked and salt-cured meats be avoided?
My take is that it is indeed best to avoid those foods processed commercially, because of the added preservatives and the unknown nature of the types of processing to which the meat has been subjected. But home-cured and smoked meats pose less of a threat, especially if not subjected to direct flame (as in grilling and broiling).
Remember that such home-processed foods have been consumed for millenia without significant risk. Salt is the primary preservative, but certain bacteria such as Clostridium botulinum (botulism) are less sensitive to salt and require saltpeter (sodium nitrate) to keep it in check if the preserved food is to be kept at room temperature.
Remember also that nitrates and nitrites occur naturally in almost all foods including vegetables in the cabbage family (2), root veggies, spinach, fruits and grains. “Basically, anything that grows from the ground draws sodium nitrate out of the soil. (5)”
From Food Reference.com (4):
“Extreme Cautions must be exercised in adding nitrate or nitrite to meat, since too much of either of these ingredients can be toxic to humans. In using these materials never use more than called for in the recipe. A little is enough.
In using these materials never use more than called for in the recipe. A little is enough. Federal regulations permit a maximum addition of 2.75 ounces of sodium or potassium nitrate per 100 pounds of chopped meat, and 0.25 ounce sodium or potassium nitrite per 100 pounds of chopped meat.
Potassium nitrate (saltpeter) was the salt historically used for curing. …
Remember, meats processed without nitrite are more susceptible to bacterial spoilage and flavor changes, and probably should be frozen until used.”
Sources:
- WCRF Expert Report Recommendations www.wcrf.org/research/expert_report/recommendations.php
- Nitrate & Nitrite Toxicity www.atsdr.cdc.gov/csem/nitrate/nitrate.html
- Nitrate & Nitirte: www.ead.anl.gov/pub/doc/nitrate-ite.pdf
- Nitrates & Nitrites: www.foodreference.com/html/art-nitrates-nitrites-7606.html from University of Georgia Cooperative Extension
- Facts about Sodium Nitrate and Sodium Nitrite: culinaryarts.about.com/od/seasoningflavoring/a/nitrates.htm