Possible Interaction: Central Nervous System Stimulants and Vitamin A

“Limited data in humans and animals indicate that excess vitamin A stimulates bone resorption and inhibits bone formation, effects that over time might lead to bone loss and fracture.”

“Animal, human, and in vitro data all indicate that excess vitamin A stimulates bone resorption and inhibits bone formation.”

“In addition, vitamin A treatment reduces matrix metalloproteinase expression and stimulates collagen synthesis in naturally aged, sun-protected skin, as it does in photoaged skin.”

“Experiments made on mice, … shown that administration of vitamin A promotes an increase in the … organs, thymus and spleen and stimulates production of the antibody-forming cells by the spleen, as well as that of … immunization with different antigens: sheep red blood cells, influenza virus, tetanus and staphylococcal toxoids.”

“ Vitamin A fed in more than ample quantities to these animals protects the animals and the cells against the toxic action of the tar and stimulates and prolongs their secondary growth.”