Women are twice as likely as men to suffer from depression. Approximately 20% of women will suffer from depression at some point in their lives. Many potential causes and contributing factors to women's increased risk of depression are being investigated by scientists. Women's higher depression rates may be linked to the biological, life cycle, hormonal, and psychosocial factors that are unique to women. Hormones, for example, have been shown by researchers to influence brain chemistry, thereby influencing emotions and mood.