Vitamin A may play a critical role in production of energy in our cells, says new research.
According to the findings, vitamin A (retinol) may play a role in the synthesis of ATP in mitochondria, the power plant of the cells (1). When vitamin A is deficient the production of energy is reduced by 30 percent.
When vitamin A supplies are adequate, the preferred energy sources are glycolysis and pyruvate production. On the other hand, when the vitamin is scarce the body turns to fat reserves, preparing the organism to win energy from fat oxidation. However, when cells are deprived of retinol, the synthesis of ATP decreases as did respiration, but such declines were reversed when retinol levels were restored, and no conversion to other retinoids was observed, showing the effect was related purely to retinol.
This answers the nearly 100-year-old question of why vitamin A deficiency causes so many diseases, the researchers commented. They said that it is also predictable that chronic deviations of vitamin A transport will lead to metabolic disease.
Vitamin A deficiency is known to cause blindness. However, the variety of cellular and molecular targets of vitamin A in the body and its many different metabolites have made it difficult to establish cause-and-effect relationships for vitamin A (retinol), except for its role on vision, primarily mediated by the major retinol metabolite, retinoic acid.
Since the intake of vitamin A is not sufficient in large parts of the population in Europe, the U.S. and Asia, the vitamin A precursor beta-carotene has an important function in providing for an adequate supply of total vitamin A.