NEW YORK (Reuters Health) - Recreational sun exposure could help prevent a type of blood cancer involving the lymph nodes called non-Hodgkin’s lymphoma (NHL), according to pooled data from 10 studies."These results...could be taken to suggest that if sun exposure does protect against NHL it is an intermittent pattern of sun exposure that is the most protective,” Dr. Anne Kricker of the University of Sydney in New South Wales, Australia and colleagues note in the International Journal of Cancer.