Premenstrual syndrome, which causes mood swings, irritability, bloating, cramps, breast tenderness, anxiety, depression and sleep disturbance is familiar to most women at some point in their reproductive years.

I reviewed the literature on PMS recently and was surprised to see that no nutrient has been as well studied for the treatment of PMS as calcium.

Blood calcium levels are lowest in the second half of the menstrual cycle due to natural fluctuations in estrogen and parathyroid hormone.

Many good studies show that 1,000-1,200mg of calcium daily from dietary sources or dietary supplements dramatically improved PMS symptoms.

Calcium should always be paired with magnesium in a ratio of 1:1 or 2:1 for this purpose, as magnesium deficiency is a common contributor to PMS as well.