The duchess - who has battled her own weight issues in the past - is in talks to team up with a British supermarket to come up with a range of nutritious food for families on a budget.
A source at supermarket chain Asda said: "We have been approached by the duchess."
Sarah - who recently moved in with a family on benefits to show how they can live on a budget - has already devised a five-point plan with healthy eating on a budget as the key.
One of her priorities is to pressurise supermarkets to provide cheaper fruit and vegetables.
The duchess, an ambassador for Weight Watchers, said: "I hope to get the tips out there so that people all over the nation from Hull to Plymouth can read about how they can change."
Sarah also plans to lobby Health Secretary Alan Johnson and Schools Secretary Ed Balls in an effort to improve the nation's eating habits.
She said: "I had to go to the heart of a real family. It means that when I do go and see Alan Johnson or Ed Balls I can go with honesty in my heart - and say I have learned from my experience and think the government should be doing it this way."
TAGS: Europe Sarah Ferguson