Professor Uauy highlighted the growing evidence of how early-life factors affect cancer risk at a World Cancer Research Fund conference last Sunday September 12.
It is believed that environmental factors that encourage obesity and weight-gain in children can all increase their risk of getting cancer.
'Someone's risk of developing cancer starts from before the time of conception. The risk factors are already operating in the mother's eggs before conception,' told The Observer newspaper.
'Yes, cancer is a genetic disease, but your chances of getting cancer are affected by the environment in which you live. So it's not just about if you smoked from the age of 12.
'But did your mother smoke? What was the water like that she drank? Is she exposed to toxins such as dioxins, which are found in the environment, and did she pass them on to her baby through her breast milk?'
Professor Uauy has been a leading advisor to the United Nations and the World Heath Organisation for several years and is believed to have compiled one of the most detailed pictures of cancer prevention yet.
He recommends that parents reduce their baby's cancer risk by eating less tinned food and reducing exposire to certain cancer-causing chemicals.
Women should stop smoking before they conceive as cigarettes can increase the rick of children having a low birth weight. Research suggests that underweight children put on weight quickly around their middles in early years which adds to the risk of cancer later on.
Professor Uauy identified a woman's ideal body mass before they conceive as being between 18.5 and 25. They should avoid alcohol and have at least 400mg of folate each day in addition to taking an iron tablet if necessary.
He added: 'Mothers-to-be only need to consume an extra 150 calories a day during the nine months of pregnancy and should not 'eat for two.'
Professor Uauy's research found that girls weighing more than 4kg(9lb) have an increased risk of breast cancer and that for every extra 500g of weight there is a six per cent increased risk of the disease.
He said that girls born with longer bodies are at a greater risk of breast cancer and that longer boys could develop prostate cancer.
It is also suggested that when the child is born parents should limit their child's television viewing and encourage exercise. And rather than telling children to 'eat up and clear your plate' he suggests they should be allowed to leave food in order to reduce obesity which has been linked to colon, breast and kidney cancer.
Breastfeeding is believed to have anti-cancer effects and babies should not eat solids until they're older than six months, Professor Uauy claimed. It was also suggested that they should not be given sweet drinks such as fruit juice which could encourage an appetite for sugary drinks which lead to weight gain.