Now this is a concern! I have such a small amount of short term memory as it is, I really can't afford to lose any. Example 'Oh I'd love a cup of tea, think I'll make one.' Look down still warm cup of tea on table in front of me. 'Wonder when I made that?'. My husband brought our 7 month old into sleep with us the other morning (it was 5am and cold). I passed him over to my husband and sleepily told him 'Just rock him a little more, he'll go back to sleep". Now I thought he'd been in bed with us for 10 minutes, looked at the clock over an hour. Like I said it's a concern. I say we ban gum or put gratuitous health warning on all packets!