Key points from article :
10% more ultra-processed in diet linked 12% more cancers detected.
Ultra-processed includes cakes, chicken nuggets and mass-produced bread.
The more of such foods people ate, the greater their risk of cancer.
On average, 18% of people's diet was ultra-processed.
French study of 105,000 people using food surveys on two days.
The study was published in the British Medical Journal.