Jenny, 47, a member of Caerphilly local public health team based at Ystrad Mynach hospital, admits there is no easy way of converting children weaned on junk to healthy alternatives.
However, she believes early years education is the way forward. And that no parent should let their child leave for school without a good breakfast.
She is full of praise for the Assembly government's free breakfast initiative, which has 353 primaries on board with another 184 due to join this term.
But she also aware schools cannot have complete control of what pupils bring in to eat. She advises parents to always fill a ham sandwich with some cucumber or tomato.
The healthy eating expert, a member of the Assembly government's food in schools working group, puts rising obesity rates down to the "microwave generation". She believes we have forgotten how to cook.
Her solution is to keep it simple to save time. Meat or fish with two veg need not be time-consuming to cook. And children should not be denied a chocolate treat sometimes, so long as sweets don't substitute for fruit or veg.