Understanding the thymus, its role in immune health, T-cells, stress, ageing and how to support your body’s natural defence system. Introduction Hidden behind your breastbone, just above your heart, is a small but remarkably important organ that plays a major role in your immune system: the thymus gland. Although relatively small and often overlooked, the thymus is essential for developing one of the most important components of your immune defence system – T-lymphocytes, commonly known as T-cells. These specialised white blood cells help your body recognise harmful invaders, coordinate immune responses and distinguish between your own healthy tissues and potentially dangerous foreign substances. The thymus is particularly active during childhood…