CBS News correspondent Father Thomas Williams says that the problem could be spiritual in nature.
"People turn to drugs for one of two reasons; either because they have so much pressure and so many difficulties in their life they need an escape or because they have a void, they have a missing center in their life and they need to fill themselves up with something," he told Early Show co-anchor Hannah Storm. "I think many of our celebrities today have both these problems. They have incredible pressures to perform, to look the right way, and on the other hand they don't have time to really see what the meaning of everything they're doing is all about."
But Williams said there have been some encouraging signs for both Spears and Lohan. Last Friday, Spears' mother Lynne Spears arrived in Los Angeles for a rumored reconciliation with her daughter and Lohan has recently spent time mending her relationship with her father Michael Lohan.
"Reconnecting with parents is a very, very important first step," he said. "Usually when people reach the pinnacles of fame and fortune, family drops out of the picture. Faith plays a very, very small role in their lives. And even friends, they're often not sure whether their friends are there for their money and popularity or are true friends. Reconnecting with family is an important first step."
Williams points to Angelina Jolie as an example of a formerly troubled star who connected to something bigger than herself and turned her life around. She realized, he said, that she is not the center of the universe. She has since become a champion of many philanthropic causes and a mother of four.
Forgiveness is also very important for recovery, said Williams but so is getting out of the public eye.
"I think that being in the spotlight 24/7 can become something that no one can withstand," he said. "They need time by themselves and maybe for that reason rehab is a very good idea."