Andra Day Had to 'Starve' Herself to Play Billie Holiday: 'Don't Do It This Way'

Andra Day has a word of advice for anyone who wants to lose weight the way she did to play Billie Holiday: "Don't."

The singer and actress, 36, had dropped 40 lbs. to "transform" into the role and better emulate Holiday.

"For the role, I couldn't look like I had been eating healthfully and exercising," Day explained to SHAPE for their September issue. "Even though Billie was stunning, hers was a 1940s woman's body that had been ravaged by drugs, alcohol, cigarettes, staying out late, and not taking care. So I had to look more dehydrated and gaunt."

Day, though, strongly cautions against following her method.

"I got to a point where I was starting to starve myself. I'd starve myself, binge eat a little, then starve myself, then binge," she said. "I've had people hit me up and say, 'How did you lose the weight?' I'm like, 'Don't do it this way.' It doesn't give you the brain clarity. It's very disorienting. It makes you sleepy and confused."

These days, Day, who won a Golden Globe for her performance as Holiday in The United States vs. Billie Holiday, is back to a more normal routine.

"Once I started to get back to a healthier state, it felt good on my system," she said. "Now, I'm enjoying the way my body feels, my mobility, all that stuff. I want to keep running, keep working with weights, and keep eating well — and also having random Cheetos moments."

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To get to that healthier state, Day got back to what makes her feel her best, like praying and exercising.

"My healthiest habit is my relationship with God," she said. "I try to spend time praying, reading, and meditating on what I read every day. I do it as soon as I wake up, or at night before I go to sleep. I sometimes do both just to keep my head focused."

And Day finds that moving her body changes her day.

"When I exercise, I have more clarity in my thoughts and in the way I function throughout the day. I feel more oriented. Working out helps me feel more capable. It helps me make better decisions. I often feel like brain fog is an issue for me, but when I'm working out regularly and drinking more water, my head feels clearer, truly. It's an exciting feeling."