A deficiency of Magnesium, caused by a low magnesium intake in the diet or reduced absorbtion in high clacium and iron diets can lead to nervous behaviour, excitability and anxiety. Also contains Vit E, B1, B2, B3, B6 and choline for optimal absorbtion. Many years of trialling this product on Pet dogs has shown a steady recovery from anxiety and fear based issues and aids in the uptake of learning new skills. A great baseline to start the training from.