Sarah Ferguson, the Duchess of York

Sarah Ferguson has her own especially made jam roly-poly flavoured tea.

Britain's Duchess of York has recently lost more than 28lbs at a boot camp on a Swiss mountain resort, but went to an expert tea-maker for help when she struggled to stay away from sweet treats such as biscuits and cakes.

Among the teas they developed together were flavours based on English desserts including jam roly-poly, rhubarb fool, strawberries and cream, Bakewell tart, chocolate torte, and mint humbug.

Two further ranges have also been developed, including 'mocktail' teas tasting of pink champagne, gin and tonic, whisky and ginger, and pina colada and a batch tackling classics such as English Breakfast and Earl Grey.

A friend says Sarah - who is said to have lost a further 14lbs by replacing sweet foods with tea - may capitalise on them.

The source told "At the moment the teas are just for her but she has had so much interest in them that she is considering whether to market them.

"There are a number of commercial opportunities she is exploring but nothing has been signed yet."

Sarah's Swiss bootcamp took 12 weeks and saw her undertake daily mountain runs and hikes with her trainer, Josh Saltzmann, as well as eating a calorie-controlled diet.