On a drizzly October morning, Nick Barnard picked me up from the tube station and drove me to a non-descript concrete warehouse row in Wandsworth, South London. There, we entered a garage like room filled with palates of Rude Health brand cereal and porridge. From here, Nick and his wife and partner Camilla Barnard are leading a revolution at the breakfast table by insisting on all natural, sustainably and artisanally produced, no-GM grains and trying to get as many people as they can to pay attention to the most important meal of the day.

How I got to Rude Health's warehouse office in Wandsworth was a result of a confluence of happenstance. Planning a trip to England, I had contacted a PR about another story that didn't go anywhere. But Sarah, the PR suggested I look into her clients, Rude Health, who made organic breakfast cereal passionately. I have nothing against breakfast, per se. But I don't often eat it and when I do, I don't think much about it. Or, I didn't until a few months ago.

This summer my wife was in hospital for the birth of our third son. In the morning, a nurse came to give her the hospital's nutritious breakfast for new mothers, which included one of those single serving boxes of cereal from a large national brand. It wasn't Froot Loops*, but one of the brands, like Rice Krispies or Corn Flakes, that most of us consider "healthy". As I am wont to do when presented with a packaged food, I decided to read the label. I was shocked. The cereal contained about five different kinds of sugar, a few types of sodium and a laundry list of multi-syllabic chemicals. Whatever grains the box contained had been processed, added to and otherwise adulterated such that the fine print ran down most of the side of the box. As it happens, Rude Health was founded by a pregnant Kate Freestone (and her husband David Vines), who wanted to bring her homemade and wholesome muesli to the public who had little too choose from on the supermarket shelves.

"They have to add sugar and salt, or their product would taste awful," Nick Barnard explained at the round table in the middle of their small loft office, above the warehouse. "We are very proud to have the words 'no added sugar or salt' on our packages and we mean it." Camilla went on to explain that not relying on sugar, salt and whatever other additives meant they had to source the best ingredients possible. For instance, their Rice Puffs (not Krispies, since the snap, crackle, pop effect is actually derived from the sugar coating) are sourced from a small scale producer in Italy's Po Valley. Sweetness is imparted with dried fruits, and flavour from the grains themselves: Rude Health's Mueslix mix has 40 (real food) ingredients – and Nick and Camilla know who grew them and where each one come from.

As important as quality is to the company, the couple went on to explain, so is availability. "No one is going to pay £10 for a box of porridge," says Nick. Their brands, which are packaged in environmentally responsible materials, retail for about $5-$7 per 500g. Rude Health is particularly excited about their partnership with Tesco, one of the UK's largest supermarkets. While the two had reservations about moving from boutique stores to a big chain (and in fact, this is their second attempt to integrate into the supermarket world), they see it as essential if they are truly going to make a difference. "The reality is," says Camilla, "that Tesco reaches something like 70% of UK postal codes." After only four years in business, Rude Health is making a national impression.

Our time is running out. There is a Swiss gentleman here to see them, who fires grains out of a sort of cannon to puff or flake them. Apparently this is how it's done, and this man does it the old fashioned way, using no additive cheats. Camilla drives me back to the tube, and tells me they are making inquires about coming to the Toronto and Vancouver markets. She thinks Canadians are ready for real cereal too. I agree, I say, if they start reading their cereal boxes.

Find out more about Rude Health, and listen to 'Nick's Rants' at their website, rudehealth.com.

*Froot Loops, which boasts something like a 40% sugar content, have recently been the centre of controversy in the United States, where the brand sported a "Smart Choice" label. Kellogs eventually promised to phase out the labels, and Smart Choice, an NGO supported by large corporations such as Pepsi Co., has suspended active operations in light of the scandal.

Malcolm Jolley is the editor of Good Food Revelation.