By Rajini Vaidyanathan
BBC News, Washington
To her fans, Oprah Winfrey is more of a friend than a talk show host.
Oprah's struggle: pictured in 1994 and earlier this month
Her intimate, heart-on-sleeve style of presenting has seen her share many personal moments with her viewers.
Her yo-yoing weight has been one such issue.
Over the years she has discussed the diets she's tried, and the pounds shed.
Now, writing in her magazine O, she tells them she has "fallen off the wagon" and weighs 200 pounds (91kg).
"I'm mad at myself. I'm embarrassed. I can't believe that after all these years, all the things I know how to do, I'm still talking about my weight.
"I look at my thinner self and think, 'How did I let this happen again?'"
The cover of Oprah's magazine features her in two different pictures.
One shows her current figure, the other her more slimline self four years ago. It's a visual and public admission that she has gained 40 pounds in the past year.
"I thought I was finished with the weight battle. I was done. I'd conquered it. I was so sure, I was even cocky.
Her current weight and height put her body mass index at 31.8, which is obese according to the Centers for Disease Control and Prevention.
It is fitting that Oprah should choose to share her latest weight woes with the world, since she has always been very open about this aspect of her life.
In 1992, she weighed 237 pounds (108kg). She hired a personal trainer and made it her goal to slim down, and completed the Marine Corps Marathon the following year.
In 1998 on her show, wearing a pair of tight fitting size 10 jeans, she famously wheeled a cart loaded with 67 pounds of fat to represent the amount she had lost on a liquid protein diet.
By 2005 she weighed 160 pounds (73kg), and had completed a diet where she starved herself for four months.
Since then, her diet pattern and weight have fluctuated. She says in her magazine that hypothyroidism - a sluggish metabolism that can cause fatigue and weight gain - are the reason she has hit the 200 pound mark.
"It seemed as if the struggle I'd had with weight my entire adult life was now officially over. I felt completely defeated. I thought, 'I give up. I give up. Fat wins.'"
"All these years I'd had only myself to blame for lack of willpower. Now I had an official, documented excuse," she said.
Writing candidly, Winfrey says that the condition sucked the life out of her, but despite feeling under the weather she continued to show up to record her shows.
"I think I hit bottom when I wanted to stay home even from a show as fun as the one we did with Tina Turner and Cher in Las Vegas.
"I was supposed to stand between them onstage, and I felt like a fat cow. I wanted to disappear. 'God help me now,' I thought. 'How can I hide myself?'"
Gayle King, Oprah's best friend, told ABC's Good Morning America that the talk show star has already had a big reaction from people who are surprised she confessed to gaining weight.
Oprah showed off her svelte figure on screen in 1988
King admits that to hear the words Oprah and embarrassed in the same sentence were "jarring" for her.
King told the programme: "This is not Oprah's first rodeo, she has gained weight, lost weight, gained weight, lost weight, and when she's ready to lose weight she does."
She hinted that although Oprah has said she is happy in herself at present, she has already begun working towards losing some weight.
"Oprah's going to do something about it... she is already in the process of doing something about it. But this isn't going to be a lifelong look for her. But the fact it's happened to her again is very stunning" King said.
Next month Oprah Winfrey is expected at Barack Obama's inauguration celebrations. Recently she talked about trying to find an outfit for the occasion.
"I had a dress on the vision board, but I'm not sure that's gonna fit... so I have to work on something else."
Oprah says her goal isn't to be thin, but to be healthy and strong.
Could this be the end of a long and very public conversation with her viewers about her weight loss?
Given her candidness on the matter before, the answer is likely to be "probably not".