# Biting on tinfoil **URL:** \ **Category:** Factual Questions\ **Created:** [October 17, 2011, 9:33pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963 "2011-10-17T21:33:53Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![jsc1953](https://avatars.discourse-cdn.com/v4/letter/j/5daacb/32.png) [@jsc1953](https://boards.straightdope.com/u/jsc1953)\ **Post date:** [October 17, 2011, 9:33pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/1 "2011-10-17T21:33:53Z")
I recently had a temporary metal crown (now replaced with a permanent, ceramic one); and while the temp was in place I occasionally would hit it accidentally with a fork. This would cause a sensation familiar to anyone who has ever done the act in the OP: not exactly painful, not really a taste, sort of like an electric shock – unpleasant, and weird. What exactly is going on in your mouth, when metal touches metal? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [October 17, 2011, 9:41pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/2 "2011-10-17T21:41:50Z")
You are creating a little battery. The dissimilar metals create the anode and cathode of the battery, and your saliva is the electrolyte. This causes a small current to flow, and your nerves are in pretty much direct contact, so it doesn’t take much current to feel it. ---
**Author:** ![jsc1953](https://avatars.discourse-cdn.com/v4/letter/j/5daacb/32.png) [@jsc1953](https://boards.straightdope.com/u/jsc1953)\ **Post date:** [October 17, 2011, 9:53pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/3 "2011-10-17T21:53:00Z")
Fascinating. Thanks, beowulff. Makes me wish my fork had a lightbulb or a propeller on the end; I could do tricks. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [October 17, 2011, 10:04pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/4 "2011-10-17T22:04:28Z")
> [@jsc1953](#): > > Fascinating. Thanks, beowulff. Makes me wish my fork had a lightbulb or a propeller on the end; I could do tricks. Well, it worked for uncle Fester… ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [October 17, 2011, 10:10pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/5 "2011-10-17T22:10:49Z")
> [@jsc1953](#): > > Fascinating. Thanks, beowulff. Makes me wish my fork had a lightbulb or a propeller on the end; I could do tricks. There is such a thing. You can sometimes find it in novelty shops. It looks like an ordinary incandescent light bulb. Stick the base in your mouth, and it lights up. ---
**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\ **Post date:** [October 17, 2011, 10:12pm UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/6 "2011-10-17T22:12:30Z")
> [@jsc1953](#): > > Fascinating. Thanks, beowulff. Makes me wish my fork had a lightbulb or a propeller on the end; I could do tricks. Look up Uncle Fester. ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 18, 2011, 2:41am UTC](https://boards.straightdope.com/t/biting-on-tinfoil/599963/7 "2011-10-18T02:41:30Z")
Details of this phenomenon and OP’s subsequent query are discussed in [If I had a lightbulb in my mouth and a lightning bolt hit me, would it incandesce?](http://boards.straightdope.com/sdmb/showthread.php?t=606005&highlight=%22Uncle+Fester%22)