A critical aspect of the body’s immune response. Inflammation is a protective response that occurs when the body is exposed to harmful stimuli, such as bacteria, viruses, damaged cells, or irritants. It involves immune cells, cell-signaling proteins, and pro-inflammatory factors. Acute inflammation occurs after minor injuries or infections and is characterized by local redness, swelling, or fever. Chronic inflammation occurs on the cellular level in response to toxins or other stressors and is often “invisible.” Inflammation plays a key role in the development of many chronic diseases, including cancer, cardiovascular disease, and diabetes.