>IMHO the fact that Asians have been consuming it in huge amounts for over a century, and yet there hasn't been any common health problems linked to it, should be enough of a clue that it's not really harmful...

This isn't really a good argument. Western people use lactose in a variety of ways such as a drink additive (tea), for cooking (cheese, cream-based sauces), and even consuming by the glass (good ol' fashion milk). However, there's a high prevalence of lactose intolerance in Asian countries. There are just some sensitivities, diseases, and reactions that are more prevalent in some ethnicities than others including lactose intolerance, sickle-cell anemia, and Tay-Sachs disease.

For the record, I keep a bottle of MSG in my pantry. I love the stuff, and the only way you'll get me to stop using it is by prying it from my cold, dead hands.