Someone seriously thought there isn't (much of) a difference between garlic and onion?? Wow, you'd think they'd only ever had elephant garlic (which is actually a leek an tastes more like onion than garlic), or something!

There is a huge difference: my digestive system can tolerate garlic just fine, but can't tolerate onion at all (unless it's the caramelized version of the sweet yellow kind, but even then it's iffy). Also, I love garlic and usually hate onion — not because of my digestive reactions to them, though; that's just a coincidence.