Many people deficient in this vitamin tire easily. Although vitamin C does not appear to directly affect energy production or pathways, it does help to the extent that it increases the body's ability to absorb iron from non-animal sources. Iron, because it transports hydrogen to oxygen in the cellular system, is important in energy production. Iodine is also important in energy production. It is a necessary constituent of thyroid hormone, which, among other functions, is involved in energy metabolism.
Potassium is important in both protein and carbohydrate metabolism.
And, of course, proteins and carbohydrates are two of the fuels from which we derive energy. If protein and carbohydrate metabolism is not efficient, less efficient energy production could result. Magnesium is also part of the process that results in the cellular production of ATP, and calcium enables the enzyme adenosine triphosphatase to help provide energy for muscle operation. Alkalinity and Energy Steve Wootton, in Nutrition for Sport, notes that one of the primary causes of fatigue in short, intensive exercise is acidity. The lactic acid then breaks down in the muscle and produces hydrogen ions.