US food safety officials have written warning letters to 16 manufacturers that claim the companies have broken labelling laws.

Two Nestle divisions, snack group Diamond Foods and pie maker Schwan's Consumer Brands are among those to have received the letters in the last ten days, according to the FDA website.

The FDA letters issue a series of warnings to the companies on the health claims made on product labels and on brand websites.

Nestle divisions Dreyer's Grand Ice Cream and Gerber ...