Mumbai, Oct 20 (IANS): Amitabh Bachchan has seen highs and lows in his over 40-year-old career and the megastar, who enjoys a strong fan base all over the globe, says insecurity from the masses is greatest challenge for celebrities.

The 72-year-old eagerly waits to see his fans gather in front of his house here every Sunday - and the crowds have only grown over the years.

Big B took to his blog srbachchan.tumblr.com Monday to share the systematic routine that he follows each Sunday morning, and how he experiences an adrenaline rush with the "roar of the anticipated crowd".

But when he returns back, he ponders if "this would be the last visit from them...would they still be interested enough to come the next Sunday or not...and on."

"Insecurity from the masses is the greatest challenge one has to face ... those that can, and many do, are blessed...I am not...for me the call from the audience is the moment of reckoning...

"They can deflate you and pick one up, they can elevate you to unknown heights and bring you down with a thump...I have seen it all...the elevation and the deflation... the plateau effect and the effect of stagnation... of the smile among audiences, of de recognition, of shame and victory from it, and the triumph of those that decided to make what you become," he added.

He says "it is a stage that often invites the lessening of the interest...a cause that shall happen to us all in the business".

"Those that can bear it and live with it in peace and understanding are my heroes," added the megastar.