Younger groups also saw higher increases in the rise of incidence in womb cancer, gallbladder disease and multiple myloma, compared with older groups.
Researchers stressed that it remains the case that cancer is far more common in older age groups. But they said the trends showed the alarming impact of the obesity epidemic.
While the United States has the highest obesity levels in the world, the UK’s levels have risen by 92 per cent since 1991, compared with a rise of 65 per cent in the US, making it the sixth fattest nation in the developed world.
Two in three adults in the UK are overweight or obese, along with one in three children leaving primary school.
Researchers said the findings, published in The Lancet Public Health journal on World Cancer Day, suggested the trends could halt or reverse decades of progress achieved in lowering cancer mortality.
One in 20 cases of cancer in the UK are linked to excess weight.
In some cancers, excess bodyweight during early adulthood could be a more important influence on cancer risk than weight gain in later life, research has found.
Tam Fry, from the National Obesity Forum, said: “There was a time when Type 2 diabetes used to be considered a mid-life disease triggered by our obesity epidemic. But that has all changed with young adults and even children’s lives blighted by the condition.
“Shockingly, if the same is happening with cancer in the US it could already be happening here. Such a discovery could negate our own recent advances in treating cancers but until the NHS seriously begins to screen for obesity, as recommended by the study’s authors, we may not know. ”