Eating reheated spaghetti bolognese could reduce your risk of cancer.
Scientists have discovered that multiple rounds of heating - plus a little extra oil - enhance the health benefits of processed tomatoes.
The technique alters the structure of the tomato molecule lycopene so that it is more easily transported into the bloodstream.
Lycopene, a powerful antioxidant, has been shown to prevent cancers and may also combat heart disease and diabetes.
Previous studies indicated that processing raw tomatoes into purees or sauces increased the benefits.
Now researchers have discovered a way to enhance this further, with a technique that is already used by families in making and reheating their spag bol.
In the average tomato, lycopene generally has a straight or 'linear' shape that hinders its ability to pass through intestinal walls into the blood.
However most of the lycopene found circulating in the bloodstream has a 'bent' molecular form. So scientists believe this kind of structure is more likely to pass into the blood when consumed.
Study leader Dr Steven Schwartz, from Ohio State University in Columbus, said: 'What we have found is we can take the red tomato molecular form of lycopene and by processing it and heating it in combination with added oil, we can change the shape of the molecule so it is configured in this bent form.'
Heat is vital to the process, but so is the addition of some fat, which helps carry the lycopene through the gut walls.