During her long career in the public eye, Oprah Winfrey has been an actor, a talk show host, a magazine mogul, a philanthropist, and more. One thing that’s been consistent over the decades, however, is the focus and speculation on her weight.

Winfrey, an investor and spokesperson for WW International (more commonly known as WeightWatchers) since 2015, told People in a new interview this week that thoughts about her weight “occupied five decades of space in my brain, yo-yoing and feeling like why can’t I just conquer this thing, believing willpower was my failing.”

She said that in addition to following a WeightWatchers plan and exercising, she also uses prescription weight loss medication “as I feel I need it, as a tool to manage not yo-yoing.”

She credited a panel discussion she participated in in September with weight loss specialists and psychologists with giving her an “aha” and she “released [her] own shame about it” and asked her doctor about the medication.

During the panel, she said she associated medication with “an easy way out.” Now, her feelings have changed.

“I realized I’d been blaming myself all these years for being overweight, and I have a predisposition that no amount of willpower is going to control,” she told People of the science of obesity, and its genetic components. “Obesity is a disease. It’s not about willpower—it’s about the brain.”

Weight loss is a chance to “live a more vital and vibrant life,” she said, and doesn’t see her own maintenance as an easy out at all. “I know everybody thought I was on [weight loss medication], but I worked so damn hard. I know that if I’m not also working out and vigilant about all the other things, it doesn’t work for me.”

Now, she said, she’s “done” with beating herself up about her body, or letting anyone else do so either.

“The fact that there's a medically approved prescription for managing weight and staying healthier, in my lifetime, feels like relief, like redemption, like a gift, and not something to hide behind and once again be ridiculed for,” she said. “I’m absolutely done with the shaming from other people and particularly myself.”