Oh, I didn't know that Oreos were vegan. Thanks for the heads up. Because, as you rightfully point out, vegan isn't necessarily healthy. Here in Germany, we have just recently had some institute assess the contents of vegan meat replacement meals. The results were quite astounding, and they led to food warnings about certain brands' products. People are frequently mislead that vegan or vegetarian are automatically healthy. Which they aren't.
My gripe with all this is that diet has become a battle field for culture wars. To many proponents of one or the other diet it is more about ethics than common sense. And common sense dictates that one's health comes first, no matter what.