Bestowing a Points of Light award each to Jean Hart and Di Archer, Theresa May said they were "making a real difference" through their charity, 'tastelife'.
She said: "You have both responded to the struggle of supporting daughters with eating disorders by creating a tremendous force for good.
"Your ambitious work with 'tastelife' is not only providing sufferers with vital support on their path to recovery, but also giving carers and families much needed guidance in how to cope with the daily difficulties of eating disorders."
Jean, who lives in Southampton, and Di, who comes from Kenilworth in Warwickshire, developed - along with a GP - their own recovery course after struggling to support their own children through eating disorders.
They said: "We are absolutely delighted that we have been chosen as 'Points of Light' for our work in combating the hideous modern curse of eating disorders.
"Through 'tastelife', lives are being changed, families remade and now, with this award, news of this work will surely spread to new areas of the country."
The programme, which was born out of Highfield Church in Southampton, was first published in July 2013. The eight weekly sessions are now run in 27 locations nationwide.
Jean and Di are encouraging people in areas currently without a 'tastelife' programme to consider running one.
Jean and Di are over the moon to be able to share the following exciting news with you... https://t.co/alji5qhHYw
— tastelifeuk (@tastelifeuk) November 22, 2018
Every weekday, the Points of Light award is given by the Prime Minister to recognise the "outstanding" work of an organisation or individual.
Anyone wanting to talk to someone in confidence about eating disorders can call the UK's eating disorder charity, Beat.
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