Spotlight keeps eating up my discspace.....

My mac has been suffering from low disc space for months and I never could be bothered to do something about it. This week, I finally got in touch with the people of CleanMyMac (great product and support team btw - I am not related) who after much research suggested that it could be the Spotlight search index and they told me how to rebuild it.

That freed up 100Gb!

After that, I thought let me just keep track of what's happening and over the last 4 days, whilst hardly using my mac the disc space is decreasing by about 1Gb a day!

Surely that's not normal / is Spotlight really that bad that it should be switched off?