Meat consumption has been often implicated in contributing to heart disease, hypertension and some forms of cancer. Most studies do not separate the types of meat consumed, but group them all together. So are all meats risky?
Most dietary guidelines recommend eating less meat and dietary recommendations from many other countries support this recommendation. But what evidence supports these claims? Most studies on this topic have mixed results.
One study from the Harvard School of Public Health looked at the different types of meat and how much of each type people actually ate. The types of meat were then separated into processed and unprocessed meats. Processed meats included bacon, salami, sausages, hot dogs and deli processed meats while unprocessed red meats included beef, lamb, and pork. No poultry was included.
The researchers reviewed nearly 1,600 studies (a meta-analysis) from all over the world that searched for a link between eating processed and unprocessed red meat and heart disease and diabetes risks but did not assess hypertension or cancer risks.
The results showed that on average, each 1.8 oz (50 grams) daily serving of processed meat per day which is equivalent to two slices of deli meats or one hot dog was associated with a 42% higher risk of heart disease and a 19% higher risk of developing diabetes.
They found no higher heart disease or diabetes risk in people who ate only unprocessed meats. (Meat lovers, rejoice!!)
They found that both categories of meats contained about the same amounts of saturated fats and cholesterol. However, the processed meats contained four times more sodium and 50% more nitrates as preservatives.
Sodium nitrate and sodium nitrite are controversial preservatives added to processed meats to 1) preserve the pink color and to inhibit botulism growth. In animals, sodium nitrite produces nitrosamines in the stomach which can be carcinogenic when consumed in large quantities.
These chemicals are found in other foods, so it is difficult to separate out their effects from processed meats alone.
Bottom line: It looks like moderation is the way to go for processed meats based on the meta-analysis. People who ate one serving per week or less of processed meat had less of a heart disease or diabetes risk.