no it's not true.
you just experianced what's called a brown out, where your computer isn't getting the voltage it needs. the fans restarted temporarily, at full speed too.
i don't know why people are so careless when it comes to power, they spend 400 dollars on an ipod, and then 100 dollars on cases and headphone, not to mention the crap you buy for your computer.
go to your local best buy and buy a UPS aka Uninterubtable Power Supply.
and make sure it supports AVR aka Automatic Voltage Regulation.
What that does is give you a few minutes after you lost power to gracefuly shut down your mac, it also feeds your machine a constant 120 volts to make it happy and extended the life of all your components.