TMZ reported earlier that the American Reunion actress was suffering from acute pancreatitis, which has symptoms including vomiting, nausea, diarrhoea and fever.
However, Reid took to Twitter today (July 21) to deny the report and to state that she was feeling "all better" now.
She wrote: "Don't worry everyone I'm all good and heathy I got a seafood poisening (sic) and hurt my back on the jetski but I'm all better thanks for caring!.. Jetski's are fun but you have to be safe they can be very dangerous!"
The Celebrity Big Brother star was photographed holding her stomach and looking concerned on Tuesday.
Sources claim, though, that she partied on yachts in Saint Tropez and visited clubs in the days leading up to her hospitalisation.