Simpson was unable to perform on the chat show as planned and had to scrap her bookings for the rest of the day, including an appearance on The Late Show with David Letterman, after her health worsened.
But Simpson honoured her commitment to appear on America's Live with Regis and Kelly! on Tuesday (23Nov10), insisting she was back on top form after kicking the bug.
She said, "I was puking my guts up yesterday. I got really sick. I don't know if it was food poisoning. One of my other friends who's out here with me, she was puking too. I think we had rotten milk so every time I think of milk now I'm queasy."
The star is expected to take part, as planned, in the Macy's Thanksgiving Day Parade in New York on Thursday (25Nov10).