Findings add to growing efforts to explain why cancer rates are increasing among younger adults worldwide Findings add to growing efforts to explain why cancer rates are increasing among younger adults worldwide Poor sleep may be fuelling the global rise in under-50s being diagnosed with cancer, two large studies suggest. The number of younger people diagnosed with the disease has risen by almost 80% in three decades. Worldwide cases of early-onset cancer increased from 1.82m in 1990 to 3.26m