Quest's Synergistic Magnesium 150mg dietary supplement provides the body with magnesium and vitamin B6, which increases its absorption. As a nutritional component, magnesium is very important for the proper functioning of muscles. Its lack can cause severe cramps and contractions in the muscles, and even severe headaches. It has also been observed that magnesium and vitamin B6 are ingredients that can help treat premenstrual syndrome (PMS), such as cramps, tension and depression.