The researchers looked at data on processed and unprocessed red meat. They defined processed meat as any meat preserved by salting, smoking curing or adding chemical preservatives. That would encompass bacon, salami, sausages, hot dogs and processed deli meats. Unprocessed meat would include beef, lamb and pork. The study did not look at poultry or seafood and vegetable protein. Their review found that for each 50-gram (1.8 ounces) daily serving of processed meat such as 1-2 slices of deli meat or 1 hot dog, there was a 42% higher risk of developing heart disease, there was also a 19% increase risk of developing diabetes.
By comparison, eating unprocessed red meat was not associated with an increased risk of developing either disease. There was not enough data to make any comment on the risk of stroke. So why the difference? Both types of meat have about the same amount of fat and cholesterol. Processed eat however has four times more salt and 50% more nitrate preservatives. As a result, it might be that difference the explains the higher risk of heart disease with the use of processed meat.
There has been a great push to reduce the amount of sodium in our diet as salt is a known risk factor for blood pressure which in turn is a risk factor for heart disease. It is also known that higher intake of total meat has a higher risk of colon cancer but the difference between processed and unprocessed meat has not bee looked at in this regard. In March of 2009, another report in JAMA from the NCI reported on the intake of red meat by quintiles-lowest fifth to highest fifth or red meat and processed meat intake. They noted that “For overall mortality, 11 per cent of deaths in men and 16 per cent of deaths in women could be prevented if people decreased their red meat consumption to the level of intake in the first quintile [one-fifth]. The impact on cardiovascular disease mortality was an 11 per cent decrease in men and a 21 per cent decrease in women if the red meat consumption was decreased to the amount consumed by individuals in the first quintile,” the authors wrote. “For women eating processed meat at the first quintile level, the decrease in cardiovascular disease mortality was approximately 20 per cent.”
The American Institute for Cancer Research and the World Cancer Research Fund called to reduce red and processed meat intake to decrease cancer incidence but suggested that future research should investigate the relation between subtypes of meat and specific causes of mortality. This study begins to examine whether processed meat is the true culprit.