Christina Applegate has shocked fans after she was photographed smoking a cigarette just months after fighting off cancer.

The star underwent a double mastectomy after learning she had breast cancer - and she quit smoking immediately. But her nicotine habit has proven too strong - and Applegate was spotted smoking in Los Angeles on Wednesday.

A source tells news show The Insider, "Christina had been a smoker for quite some time. She stopped smoking when she received her health news last year but, as everyone knows, it's difficult to break an addictive smoking habit. Considering all the stress she's had over the years, she had that occasional weak moment which has led to the occasional cigarette. We need to remember she's only human."

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(This news article provided by World Entertainment News Network)