New Delhi: Anjali Hooda, sister and doctor of Randeep Hooda who collapsed on the sets of superstar Salman Khan-starrer "Sultan", says drastic weight change is difficult "mentally and physically".

Randeep collapsed on Sunday evening following a severe attack of appendicitis. He underwent surgery at Fortis Hospital here on Monday.

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Asked how difficult it is for an actor to mould his body for a character which needs a drastic weight change, Anjali, a specialist in metabolism, told IANS: "For an actor, it may not be difficult because he is very motivated. But for his body it is very difficult because it doesn't understand starvation. It is very difficult mentally and physically".

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Anjali also added that the "motivation is so high for these people (actors) that they don't realise the implications" of fluctuating weight change.

Asked if sudden fluctuation of body weight was the reason for Randeep's health problem, she explained: "It's (appendicitis) not directly related to fluctuation of weight. But yeah, weight loss of extreme type can cause faeces becoming hard because there is no fibre. This is minimal of a problem that can happen and this is a good example for people to know..."

Anjali also mentioned that this is a minute problem, but such major weight loss programmes can cause other "unforeseen problems" in the body.

Randeep's ailment could be related to the "extreme make-over" he had for Omung Kumar's "Sarjbit", for which he "put his life on the line", she said.

"Sarbjit" is a biopic on Sarabjit Singh, an Indian farmer who was convicted of terrorism and spying in Pakistan and was sentenced to death. He was attacked by inmates at a prison in Lahore in April 2013 and died a few days later.

Randeep will be seen essaying the title role of Sarabjit and had to undergo major weight loss for the character.

The "Kick" star was given enough food to "sustain for the day" while shooting the biopic.

"So we were giving him very less calories and we were making sure that he doesn't get any blood related issues like electrolyte problems and lack of energy," she said.

Anjali added that the inflammation of appendix is "not directly related to weight loss, but can happen due to lack of fibre, calories and water... it can lead to anything".

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IANS