Study Reveals Diet and Weight Mediate Link Between Depression and Headaches - Video

Chronic headaches and depression often travel hand in hand, but what actually links the two? A new study published in Scientific Reports suggests that the connection might run deeper than shared symptoms. Researchers found that higher body mass index (BMI) and lower dietary iron intake may be key biological bridges linking depression to chronic headaches, while physical activity doesn’t seem to play a direct role.

Depression is one of the world’s leading mental health conditions, affecting mood, energy, and overall well-being. Chronic headaches, like tension-type headaches and migraines, are also widespread and often occur alongside depression, creating a cycle of pain and poor mental health. Scientists have long suspected that lifestyle factors such as diet, weight, and exercise influence this connection. The new study provides evidence for how these factors may fit together.

The research team used data from nearly 10,000 adults aged 35–65 participating in the Ravansar Non-Communicable Disease (RaNCD) cohort in western Iran. Through in-person interviews and standardized health assessments, they collected detailed information on participants’ mental health, body weight, physical activity, and diet. Physical activity was expressed in metabolic-equivalent task hours, dietary iron intake was calculated through food frequency questionnaires, and depression was diagnosed through clinical evaluation or antidepressant use. Chronic headaches were defined as headaches occurring at least 15 days a month for three consecutive months.

Statistical “path analyses” tested whether BMI, iron intake, or physical activity explained the depression–headache relationship. The results showed that individuals with depression had higher BMI, lower iron intake, and a greater likelihood of chronic headaches compared to those without depression. The models confirmed that both higher BMI and lower iron levels partially mediated this association, while physical activity did not act as an independent pathway once other factors were considered.

Importantly, physical activity still contributed indirectly by influencing weight and iron intake, reinforcing its overall health benefits. The authors note that while their study cannot prove causation, it underscores how interconnected mental health, nutrition, and physical health truly are.

REFERENCE: Hosseini, F.A., Bagherian, S., Shaygan, M., Cañete-Massé, C., Bonyani, M., Najafi, F. (2025). Mediating effects of physical activity, BMI, and dietary iron intake on the relationship between depression and chronic headaches. Scientific Reports. DOI: 10.1038/s41598-025-31993-0, https://www.nature.com/articles/s41598-025-31993-0