Polydimethylsiloxane, or PDMS as we will call it from here on out, is indeed a common food ingredient ... you'll even find it at your favorite fast-food haunts (we would name them, but we're pretty sure you'll never go back, and we think their Seven Layer Burritos are definitely worth frequent visits ... oops!).
Aside from its use as a food additive, other interesting places you'll find PDMS include Silly Putty, anti-foaming agents, breast implants, dry-cleaning solutions, silicone and head-lice treatments. Hey, we never said it was a cohesive list! Which reminds us ... it's also a bonding agent. Is there anything PDMS can't do?