The Meat Dilemma

For several decades now, the FDA has been admonishing the American people to eat less fat. In particular, they claim, Americans eat too much meat, which is a major source of saturated fat. As such, we've been instructed to avoid eggs, red meat, and animal fats as much as possible. However, in the past few years, it has become increasingly clear that fat, per se, is not the problem. Eggs have been reborn as a low-calorie source of protein and "good" fat; butter, it turns out, is actually better for us than trans-fat-laden margarine; and now, red meat has seen its vindication, too.

A recent meta-analysis published in Circulation, the journal of the American Heart Association, has shown that red meat consumption is related to neither cardiovascular heart disease (CHD) risk nor diabetes risk. (1) Instead, the study found that processed meat consumption was associated with a whopping 42% increased risk in CHD and a 19% higher risk of diabetes. By processed meat, the authors mean red meat products that were smoked, cured, or salted, or that had added preservatives (including nitrates).

So what is responsible for the difference in toxicity? The authors considered the nutritional differences between processed and unprocessed red meats on average. They found that the two types of meat had similar levels of saturated fat, but processed meat had slightly less protein, slightly more fat, 4 times more sodium, and 50% more nitrates and nitrosamines. As excessive sodium intake has been implicated in high blood pressure, a primary risk factor for heart disease, and nitrates have been shown to exacerbate atherosclerosis (among other pathologies), the deleterious consequences of processed meat consumption are likely due to an excess of sodium and nitrates.

Though caution in interpreting the results of such epidemiological studies is warranted, the authors of the article were remarkably thorough. They noted that the results of the study, it might be argued, could be chalked up to demographic differences in consumers of processed vs. unprocessed meat. But this was not the case; the studies in the authors' analysis all controlled for socioeconomic factors and, moreover, the demographic differences between the groups were small to begin with. Consequently, it is difficult to attribute the study's results to any factors external to meat processing.

In light of this remarkably comprehensive (and readable, I might add) analysis of twenty separate studies, it might just be a good idea to skip the hot dogs and grab a pound of top sirloin instead, next time you visit the grocery store. Your arteries will thank you.

(1) Micha, R et al., Red and Processed Meat Consumption and Risk of Incident Coronary Heart Disease, Stroke, and Diabetes Mellitus. A Systematic Review and Meta-Analysis, 2010.