Stress can accelerate the progression of neurological and neuropsychiatric diseases. In fact, chronic stress is linked to hypertension, anxiety, and depression, which increase oxidative stress and promote neuroinflammation, which are factors involved in age-related dementia. Curcumin, the active principle from Curcuma longa, plays anti-inflammatory and antioxidant roles and mitigates detrimental effects of stress. Stress often promotes depression, activates distinct neuronal circuits in the brain and provokes neuroinflammation and neurodegeneration. Acute stress has short-term effects on the immune system, including changes in the number and composition of circulating monocytes, and increases cytokine levels. Mediators of inflammation have been found to be higher in individuals with depression, while stress-induced increase in blood monocyte levels is independent of monocyte subtypes. Stress affects monocyte levels in pathological chronic stress-related conditions, including anxiety and depression or post-traumatic stress disorder.

Since pharmacological anti-stress drugs have some adverse effects, long-term curcumin supplementation (1800 mg/day) over 90 consecutive days in patients with moderate anxiety prevented sCD14 increase casued by stress; additionally, MCP-1-induced overproduction by anxiety as a chemotactic mechanism can activate monocytes in certain neurological conditions. Both increases in sCD14 and MCP-1 levels were reverted by curcuminoids in patients with anxiety. Thus, curcumin prevented anxiety behaviour, due to decreased cortisol and reduced systemic cytokine levels in patients with moderate anxiety.