Lettuce be glad for a cast-iron stomach

I had yesterday off work owing to a rather horrible bout of post-Mexico stomach "issues" that left me feeling rather seedy. In any case, I only trusted peppermint tea, small cups of coffee, and water to nourish my system. Given the obvious light-headedness in which such a diet resulted, I figured staying home was truly the best medicine.

I've come to work today, feeling a little thinner to be honest (woohoo) but managed to have a rather surreal remote conversation with my boss, the essence of which follows:

Boss: Are you feeling better? What did you eat?
Me: Yes, much better thank you. Not sure what I ate, but I will try not to do it again.
Boss: I bet it was the lettuce. Did you eat the lettuce?
Me: [slightly shocked that this would be his first go-to gastro nastie] Uh, yes I had salad on the buffet but they would have been careful not to wash that in tap water.
Boss: You can't be sure of that; you should have asked. Did you drink the water?
Me: Oh no, I know better than to do that [I omitted sharing with him the amount of tequila I drank]. After the travelling I've done incident-free, perhaps it was just my time to get sick...
Boss: Nonsense, it happens all the time. Right well it's good that you're good, you should count yourself lucky. Now, anyway.
Me: Yep, I do. After yesterday's efforts I'm just grateful to be alive. Groan.