AKG is a key intermediary within the Krebs cycle or citric acid cycle. The Krebs cycle is a series of chemical reactions to release the stored energy from the derivatives of carbohydrates, fats, and proteins. AKG regulates the speed of the Krebs cycle, but has multiple other functions, including amino acid production, cellular signaling, regulating gene expression, and powering stem cells. AKG is also involved in increasing circulating levels of insulin, growth hormone, and insulin like growth factors. Declining AKG means that the mitochondria are able to produce less energy. Declining energy levels adversely affect every cell, tissue, and organ in the body, decreasing brain function, heart, liver, kidney, gut, muscle, and bone activity. Declining energy levels decrease the regulatory systems that control inflammation and oxidative stress. Declining AKG levels decrease stem cell numbers by as much as 75%, and stem cell function can be reduced by as much as 90%.