Did Sarah Palin have an affair? John McCain's campaign has threatened legal action against the National Enquirer for running a story saying Vice-Presidential candidate Sarah Palin had an affair with her husband's business partner. "The smearing of the Palin family must end. The allegations contained on the cover of the National Enquirer insinuating that Gov. Palin had an extramarital affair are categorically false. It is a vicious lie," said McCain senior adviser Steve Schmidt. "The efforts of the media and tabloids to destroy this fine and accomplished public servant are a disgrace. The American people will reject it."

Report: David Duchovny didn't cheat: Despite rumors that the actor entered rehab for sex addiction because he had been caught having an affair with his tennis instructor, a close friend of Duchovny's says he did not check in because of an extramarital fling. According to the source, Duchovny's problem has been with excessive Internet porn and his wife, Tea Leoni, had been aware of it for years. 

Thinking hard makes you fat: Intellectual activities make people eat more than when just resting, says a new study published in the journal Psychosomatic Medicine. When researchers asked students to relax, summarize a text, or complete a series of memory, attention, and vigilance tests, those who had performed the test consumed 253 more calories (30 percent more) than the couch potatoes. Those who had summarized a text consumed 203 more calories than the resting group. Lead authors surmise hard thinking triggers a chemical reaction that makes the body store fat.

New York school teacher vanishes: A 23-year-old teacher has disappeared from her apartment days before classes started. A friend last saw Hannah Upp on Friday afternoon as she was about to leave her Manhattan apartment for a school function at Thurgood Marshall Academy where she is a Spanish teacher. Upp last used her debit card that day to see a movie alone and told friends she was spending the weekend at her mother's home in Philadelphia. When she hadn't returned Monday, her roommates found her keys, phone, ATM card, MetroCard, wallet and passport in her room. Friends and family have launched a frantic search.

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