System/organ | Energy expenditure per day (kJ/day) |
---|---|
Muscle at restb | 2,500 |
Central nervous system (brain and spinal cord) | 2,500 |
Immune system in a quiescent statec | 1.600 |
Liverd (including immune cell activity) | 1,600 |
Heartb | 1,200 |
Gastrointestinal tract (including gut immune system, without liver, kidney, spleen)d | 620 |
Kidneys | 600 |
Spleen (erythrocytes plus leukocytes; 90% anaerobic) | 480 |
Lungsd (including lung immune system) | 400 |
Skind (including skin immune system) | 100 |