Women aged 25 to 45 who were exposed to several traumatic life events like the death or divorce of parents during their childhood or teenage years, or the later loss of a spouse, or moderate traumas such as losing a job or a financial crisis are at higher risk for breast cancer and should be treated accordingly, according to Israeli researchers. In a study just published on-line in BMC Cancer (www.biomedcentral.com), Prof. Ronit Peled, Orly Siboni Samocha and Ilana Shoham-Vardi of Ben-Gurion University's health sciences faculty and Devora Carmi of the University of Haifa, 622 women aged 25 to 45 were interviewed. Of these, 255 had been diagnosed with breast cancer and 367 were healthy. The results showed a clear link between their psychological outlook and risk of breast cancer, with optimists 25 percent less likely to have developed the disease. Conversely, women who had suffered two or more traumatic events had a 62% greater risk, the authors wrote. Since 1983, studies have suggested an interaction between severe life events, psychological distress and the development of cancer, the researchers wrote. However, these associations are still under dispute. Happiness and optimism may play a role against breast cancer in younger women, they suggested, while adverse life events can increase the risk of developing the disease, according to the study in the British journal. The researchers suggested that psychological stress could contribute to the increase of the risk of cancer by modifying cell responses to environmental factors, but they added that the mechanism in which the central nervous, endocrine and immune systems interact and how behavior and/or external events modulate these three complex systems is "not fully understood." However, exposure to a number of events (severe or even mild to moderate) was significantly associated with the disease. This suggests that stressful events do not protect women from the effect of additional events, and even "moderate or mild" events, seem to have a cumulative effect, they wrote. The researchers state that their study was not perfect, as women with breast cancer were interviewed about a year after their diagnosis, "which may color their recall of their past emotional state somewhat negatively." In addition, only 25% of those cancer patients asked to participate actually did. But according to Peled, "We can carefully say that experiencing more than one severe and/or mild-to-moderate life event is a risk factor for breast cancer among young women. On the other hand, a general feeling of happiness and optimism can play a protective role." She and her colleagues suggested that the relationship between happiness and health "should be examined in future studies and possible relevant preventive initiatives should be developed."