How Debra Messing Lost 20 Lbs. – Unintentionally
04/24/2014 AT 09:30 AM EDT
The actress, 45, tells ABC News that she switched to a healthy diet because she had low energy, and the weight just fell away.
"About two to three years ago, I made a very, very big change [to] the way I approach nutrition. I think it made a big difference in how I look or at least how I'm perceived to look," says the mom to 10-year-old son Roman.
"I lost like 20 lbs. – it wasn't my intention, that wasn't why I made the change. I made the change because I was just tired all the time," she says.
The former Smash star says she was raised on a poor diet and continued with those bad habits.
"I grew up on fast food and candy every day," she said. "Pizza and french fries and burgers – I love food and I've always loved food. Vegetables were not part of my life at all!"
But Messing became good friends with veggies when filming a new pilot, The Mysteries of Laura. Each morning, she would have a green juice made of kale, spinach, celery and cucumber – plus ginger and lemon for taste.