Drew Barrymore is taking fans on a journey into her weight loss process! On Tuesday, Barrymore posted some “before and after” photos and video on Instagram of herself working out. She also credited her trainer, Marnie Alton, for helping her accomplish her goal and being a key support system along the way. 

"This woman is my long time teacher and dear important friend," Barrymore said of Alton at the start of her post. "She has helped me. Healed me. Encouraged me to keep going when I felt like being strong was an insurmountable task."

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Barrymore’s weight loss for her Santa Clarita Diet role

Barrymore explained why she was so intent on losing weight to play zombie “Sheila Hammond” on the Netflix series Santa Clarita Diet. “If a woman was really eating just protein and nothing else, she would lose weight,” Barrymore said, rationalizing her character’s metabolism. “It gave me this intense responsibility that I said I want to fulfill to be Sheila and then there was like no excuses”.

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When Barrymore shared with Alton that she wanted to undergo a fitness transformation for her new role, her trainer was up to the task.

"We have known each other for about 15 years and when I told her I wanted to transform my body for #SANTACLARITADIET she helped me,"  Barrymore shared. “Every spring, when I would start training to become #SHEILAHAMMOND Marnie was the one who got me there. I lost 20 pounds and trained like a mother”.

See Drew Barrymore’s amazing “before and after” pictures and videos of her weight loss journey here!

'Doctor Who' Season Finale - This Is What We Know

Get excited for a big two-part story arc, Whovians!

'Doctor Who' Season Finale - This Is What We Know