A study of 401 overweight women in California looked at the effectiveness of a phone and Internet based behavioural intervention designed to improve behaviours such as diet and exercise. Previous studies have shown that psychotherapy for depression can be delivered successfully by telephone or via the Internet and other studies have shown that exercise and weight loss can help people to feel less depressed so as well as their weight and exercise levels the study also monitored the women's mood. After 12 months those receiving the intervention significantly decreased their depression scores compared to a control group and those with probable depression showed clinically important improvements. The participants who engaged more readily with the intervention were more likely to reduced their depression scores.
Kerr, Jacqueline ... [et al] - Randomized control trial of a behavioral intervention for overweight women: impact on depressive symptoms Depression and Anxiety 25(7), 555-558