1985 commercial for Shreadded Wheat.

Shredded wheat is a breakfast cereal made from whole wheat. It comes in two sizes, bite sized (³⁄₄ × 1 in), and full size, which may be broken into small pieces before milk is added.

Both sizes are available in a frosted variety, which has one side coated with sugar and usually gelatin. Some manufacturers have produced “filled” versions of the bite-size cereal containing a raisin at the center, or apricot or cranberry filling.

In the United States, shredded wheat is most heavily advertised and marketed by Post Cereals, which acquired the product in 1993 through its parent company, Kraft Foods, buying it from its long-time producer Nabisco. Kellogg’s sells eight varieties of miniature, or bite-sized, shredded wheat cereal. Natural and organic manufacturer Barbara’s Bakery makes an all-natural version of shredded wheat. In the United Kingdom, the Shredded Wheat brand is owned by Cereal Partners, a Nestle/General Mills company, although there are many generic versions and variants by different names. It was first made in the US in 1893, while UK production began in 1926.

“Never Eat Shredded Wheat” is a common childhood mnemonic for remembering the Cardinal Points on a compass.

UK
History
The original company opened a factory in Welwyn Garden City (UK) in 1926, which became part of Nabisco in 1928.  The tall concrete cereal silos that form part of the factory are a local landmark and are listed structures, built by Peter Lind & Company of London. In 1988 Nabisco sold the UK site to Rank Hovis McDougall (who made own-label cereals for supermarkets), whose breakfast cereals division briefly became The Shredded Wheat Company. In 1990 RHM sold the site to Cereal Partners. Now, all Shredded Wheat is made at Staverton near Bath, as the Welwyn Garden City site was shut down in 2008. Also, “Bitesize”, “Fruitful” and “Honey Nut” Shredded Wheat are made in the UK.

Advertising
Shredded Wheat has a particular place in UK popular culture due to a long-running TV advertising campaign. The Three Shredded Wheat advert suggested that the cereal was so nourishing that it was impossible to eat three. Even a black hole was shown as exploding when the third biscuit was sucked into it. Phrases such as I bet you can’t eat three and He must have eaten three were in common use as humorous remarks in the 1970s.   A later UK poster advert for Carling Black Label showed a bowl with four Shredded Wheat and the caption “I bet he drinks Carling Black Label”.

Bernard Manning, the UK comedian, made this into a joke: Why does Arthur Scargill eat three Shredded Wheat? Answer: He eats two, the other one he puts on his head; (Scargill was known for having a particularly bad toupee).

Trademark of the term “shredded wheat”
In the United States Supreme Court case Kellogg Co. v. National Biscuit Co. (1938), National Biscuit Co. sued Kellogg, attempting to enjoin Kellogg from using shredded wheat as a trade name and from manufacturing the cereal in its pillow-shaped form. The Supreme Court ruled that shredded wheat was generic and not trademarkable; and that in any case, when the first patent for shredded wheat machinery expired in 1912, the right to apply the name “shredded wheat” to the product passed into the public domain along with that patent.

^{Info gleaned from Wikipedia}