Intermittent fasting, increased fluid intake and proper sleep schedule helped actor R. Madhavan lose a significant amount of weight within 21 days after undergoing a body transformation for the 2022 film Rocketry: The Nambi Effect, he said on Thursday.

“Intermittent fasting, heavy chewing of food 45-60 times( drink your food and chew your water) .. last meal at 6.45 pm .( only cooked food -nothing raw AT ALL post 3 pm ) .. early morning long walks and early night deep sleep( no screen time 90 min before bed) … plenty of fluids .. lots of green vegetables and food that is easily metabolized by your body and healthy. Nothing processed at all. ALL THE VERY BEST,” the 54-year-old actor wrote alongside an old video of him discussing his weight transformation.

The video shared by an X user shows Madhavan revealing his diet regime for weight loss.

“And I only ate food that was good for my body. No exercise, no running, no surgery, no medication. Nothing,” the Shaitaan actor says in the video before showing a picture of him before the transformation and after. “This was me before directing the film as my real stomach, and after 21 days, this was me,” he said.

“Everything is done with food,” he says firmly. “Sorry I’m sounding like a doctor. But hey, you know what, a great part of my life is science,” he adds.

Rocketry: The Nambi Effect was Madhavan’s directorial debut, which won him the National Award for best feature film. The biopic focuses on the life of former ISRO scientist S. Nambi Narayanan.