The Allied Bakeries-owned brand is rolling out its Great White loaf this month, backed by a £6.7m campaign from April, which it claims will "revolutionise" the bakery sector.
With many consumers abandoning white bread for health reasons, Kingsmill believes the new product will create a new segment worth £100m within three years.
The brand is will push the health benefits of the Great White loaf, and has released a report arguing that seven out of 10 men, nine out of 10 women, and eight out of 10 children fail to eat enough fibre in the UK.
A forthcoming 40-second TV ad, by Contagious London, will again feature comic actor Jon Thomson as the father in what the brand has dubbed the "Kingsmill family", based on an insight into the role bakery products play in family life.
Darren Grivvell, director of brands at Allied Bakeries, told Marketing the aim is to transform Kingsmill into a more "emotional" brand for customers.
He said: "We think this a natural move for Kingsmill, given our strength in healthy breads. It’s another great product for families, which is our heartland, and we think the communication is a real step on from what we’ve had in the past, much more resonant and emotional about the role of that Kingsmill plays."
Lydia Freeman, senior brand manager for Kingsmill, added: "This new product will give consumers permission to eat more white bread, so we will win customers from other categories, such as cereals. It gives us a point of difference."
In the 12 months to October 2013, Kingsmill enjoyed a 3.3% growth in sales, up to £358m for the period. It is the third biggest-selling bread brand, behind Hovis and clear market leader Warburtons, according to Nielsen.