US researchers say they have created a "virtual" model of all the biochemical reactions that occur in human cells.
They hope the computer model will allow scientists to tinker with metabolic processes to find new treatments for conditions such as high cholesterol.
It could also be used to individually tailor diet for weight control, the University of California team claimed.
A team of six bioengineering researchers at the University of California analysed the human genome to see what genes corresponded to metabolic processes, such as those responsible for the production of enzymes.
They spent a year manually going through 1,500 books, review papers and scientific reports from the past 50 years before constructing a database of 3,300 metabolic reactions.
The information was then used to create a network of metabolic processes in the cell, similar to a traffic network.