Drew Barrymore Shows Off Pictures And The Secret To Her Dramatic Weight Loss

Kristine Lofgren

Drew Barrymore has transformed her body with a 20-pound weight loss, and now the actress is sharing the secrets to her success with a series of before and after photos.

Barrymore posted pictures of her and trainer Marnie Alton on Instagram goofing around, working out and motivating each other to push harder.

"This woman is my long time teacher and dear important friend. She has helped me. Healed me. Encouraged me to keep going when I felt like being strong was an insurmountable task," Barrymore wrote.

The first image shows Alton hugging Barrymore from behind as the actress laughed. In the next image, it's all business, as Barrymore works out her core on a floor mat. The image shows Barrymore before in a red shirt and brown tights with a cast on her leg. Next to that picture, it shows her 20 pounds lighter -- looking more fit and trim in the same position on the floor.

Other photos in the series show motivational quotes, and Barrymore doing yoga and sweating on the mat.

"I lost 20 pounds and trained like a mother," Barrymore says of her transformation.

Barrymore went on to praise Alton, who she says she has known for 15 years, and who she turned to when she wanted to get fit for her Netflix show the Santa Clarita Diet.

"She is poetry in a human being. The best heart. Her priorities are in the right place. She is humorous and so so so knowledgeable about our bodies. I love her. Inside and out. Her classes are always booked up and we all love to run to her for her spirit and leadership for all things healthy," Barrymore gushed.

She went on to say that she appreciated Alton because she was motivating not only from a physical perspective, but from a mental one as well. She says that Alton helps people become their best selves in a healthy and sane way without the "terminator" mentality.

Barrymore later posted another image promoting Alton's upcoming pop-up classes in New York City.