I’m not sure which was more offensive and misleading: a recent anti-meat TV ad from an animal rights group posing as a mainstream cancer-prevention charity or the opinion essay from Susan Levin that defended it (“Dogs of death,” Opinion and Commentary, Sept. 14).

The ad itself was bad enough, featuring kids who claimed to have cancer (they didn’t) in order to promote the myth that colon cancer begins with the first hot dog you ever eat (it doesn’t). But Levin’s op-ed stretched the truth even further, suggesting that there’s something unique about processed meat that warrants a skull and crossbones. (There isn’t.)

For the record, the single biggest study ever conducted of meat and colon cancer diagnoses, a 2004 Harvard University project, found no link at all between the two.

Meanwhile, cancer rates in the United States are decreasing every year. Americans are living longer than ever. And India, arguably the most vegetarian country on Earth, has a life expectancy five years shorter than ours.

A recent study from Oxford University found that eating a strictly meat-free diet dramatically increases the risk of “brain shrinkage.”

Now that’s some food for thought.