Amy Winehouse died of bulimia, not alcohol and drugs, her brother says.

Almost two years after British singer Amy Winehouse died, her brother has come forward to speak about his sister's bulimia. Alex Winehouse says

Winehouse's  struggle with substance abuse was not to blame for death at 27.

"She suffered from bulimia very badly," he told the Observer recently. "That's not, like, a revelation-you knew just by looking at her...She would have died eventually, the way she was going, but what really killed her was the bulimia...Absolutely terrible." Alex Winehouse, 33, said.

He believes the eating disorder made his sister more vulerable.

"Had she not have had an eating disorder, she would have been physically stronger."

He says that when "Rehab" singer Winehouse was 17, she and a group of friends developed a problem with bulimia--and Amy never stopped. She was addicted to binging and purging repeatedly.

"They'd put loads of rich sauces on their food, scarf it down and throw it up," Alex said. "They stopped doing it, but Amy never really did...We all knew she was doing it, but it's almost impossible [to tackle] especially if you're not talking about it."

Alex broke his silence to talk about his sister's struggles with bulimia. "I just want to try to raise awareness of bulimia. It's a real dark, dark issue," Alex Winehouse said.

He spoke to U.K. magazine The Observer as the "Amy Winehouse: A Family Portrait" exhibit opens at London's Jewish Museum.

He added that Amy Winehouse's charity, which is run by her dad, Mitch Winehouse, currently contributes to charities focused on eating disorders.

Amy Winehouse died at 27 in July 2011. The official cause of death was alcohol poisoning. She was best known for her Grammy-winning album "Back To Black"-and her unique beehive hairdo and eyeliner.