Contrary to her son's claims, cancer-stricken actress Farrah Fawcett doesn't weigh 86 pounds, her physician Lawrence Piro tells Usmagazine.com.

Redmond O'Neal, 24, made the shocking claim to a judge during a drug-related hearing last week, but Piro tells Us he weighed the 5'6 1/2" actress, 62, a week ago, and "she was 101 pounds," which he calls "a reasonable weight" under the circumstances. Although that is down some from her normal weight, "she's continuing to eat and trying to gain weight," Piro tells Us. "It's a struggle that all cancer patients go through."

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Piro says he has been trying to keep Fawcett's "nutrition as robust as possible through treatment. She's continuing to eat as much as she can, and we're continuing to have a good array of nutritious food offerings so she can do that." "All cancer treatments tend to erode your appetite a little bit," he tells Us, adding that, under treatment, bodies don't always process food as efficiently as they might otherwise. "That's why nutrition is a very active part of any treatment," he said. "We're paying a lot of attention to that with her, and she's very aware of that."

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Luckily, Fawcett has "lived a very healthy lifestyle all of her life, and nutrition has always been important to her, so she's continuing to work on that." Fawcett was released from a Los Angeles hospital on April 9 as she wages a long battle with anal cancer, first diagnosed in 2006. "She has gained some of her strength back and she's able to walk around," Piro tells Us. "She's continuing to fight the battle."

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