Researchers at the German Cancer Research Center have found that vitamin A deficiency can damage blood stem cells.

Specialized cells in the skin, intestines, or blood have a short lifespan and need to be replenished. They come from adult stem cells that divide continuously to survive.

In 2008, researchers discovered a special group of stem cells in the bone marrow that are mostly dormant and only become active when fighting viral or bacterial infections, severe blood loss, or reactions to chemotherapy. When their activity is done, the body sends the most potent stem cells back into “hibernation.”

Researchers have identified the mechanism that activates and deactivates stem cells. They found that retinoic acid, a vitamin A metabolite, is critical to this process. Without retinoic acid, active stem cells cannot return to a quiescent state and become specialized blood cells.

In studies in mice, the researchers found that stem cells were reduced if retinoic acid was lacking.

“If we feed mice a vitamin A-deficient diet over time, this leads to a loss of stem cells,” said Nina Cabezas-Wallscheid, lead author of the study. “This is the first time we have been able to demonstrate that vitamin A has a direct effect on blood stem cells.”

The study sheds light on previous research that has shown that vitamin A deficiency weakens the immune system.

“This shows how important it is to get enough vitamin A from a balanced diet,” said Cabezas-Wallscheid.

The researchers hope that the findings could play an important role in cancer treatment because cancer cells, like stem cells, are in a state of “hibernation” and their metabolism is completely shut down, making them resistant to chemotherapy.