By Daniel Hunter

Weight Watchers International has seen shares jump 16% after an unnamed activist hedge fund launched a takeover bid.

The US-based company has seen shares plummet 85% this year after shareholder criticism that it was not doing enough to keep up with competition and health trends.

Profits fell 52% to $2 billion (£1.3bn) last year. And although media reports were slim, they were enough to send shares up.

It is understood that the unnamed hedge fund has bought Weight Watchers' loans, which are due to repaid in April 2016, and has now approached potential partners for a full takeover.