Do Organs Use Energy?

Yes, organs use energy to function. This energy is primarily derived from glucose, the body's main energy source, but also from fats and proteins. The amount of energy used varies significantly depending on the organ and its activity level.

Energy Consumption by Organs

• The liver and spleen are major energy consumers: A significant portion (approximately 75% of daily calories burned) is used by these organs for basic functions. [1]
• The brain is a highly energy-demanding organ: It uses a substantial amount of the body's total energy, accounting for up to 20 percent. [8] It relies heavily on glucose as its primary fuel source. [2] While crucial, excessive glucose can negatively impact brain function. [2]
• Other organs also require energy: All organs and tissues in the human body require energy to maintain their structure and function. [3] Adipose tissue (body fat) stores extra energy for later use. [7] The digestive system processes food to provide energy. [10]

The energy consumption by organs isn't solely determined by their size; organs with higher metabolic rates consume more energy. [3] Furthermore, viral infections, like COVID-19, can cause lasting damage to cellular energy production within various organs. [9]

Sources of Energy for Organs

The human body utilizes three main types of molecules for energy production: fats, proteins, and carbohydrates. [5] Glucose, a type of carbohydrate, plays a central role as the primary energy source for cells, tissues, and organs. [4]

[1] The largest fraction of energy goes to the liver and spleen, with the brain coming next. About 75% of the calories burned in a day go into these basic functions.

[2] https://hms.harvard.edu/news-events/publications-archive/brain/sugar-brain

[3] https://pmc.ncbi.nlm.nih.gov/articles/PMC2980962/

[4] https://medlineplus.gov/carbohydrates.html

[5] https://www.nature.com/scitable/topicpage/dynamic-adaptation-of-nutrient-utilization-in-humans-14232807/

[7] https://my.clevelandclinic.org/health/body/24052-adipose-tissue-body-fat

[8] https://www.scientificamerican.com/article/why-does-the-brain-need-s/

[9] https://www.nih.gov/news-events/nih-research-matters/sars-cov-2-can-cause-lasting-damage-cells-energy-production

[10] https://www.cancer.gov/publications/dictionaries/cancer-terms/def/digestive-system