Dr. Susan Thys-Jacobs is a practicing endocrinologist and leading expert in Premenstrual Syndrome (PMS) research. For over 20 years, she has worked passionately and extensively to solve this pressing medical problem. She has consistently been committed to proving that women need not suffer with monthly menstrual symptoms.


In the early 1980s, she noticed the similarities between menstrual cycle symptoms and those symptoms exhibited by people with dramatic calcium deficiency.

She was lucky. New methods for testing vitamin and mineral levels in the blood had just been introduced which allowed her to test her theory – that menstrual cycle symptoms were simply a nutrient deficiency in the body.

Her early investigations were positive and her discovery generated immediate interest from large pharmaceutical companies. In partnership with one of those companies, Dr. Thys-Jacobs conducted the largest ever study of the effect of calcium on PMS. It demonstrated conclusively that calcium can indeed relieve PMS.

Replacing the calcium alone reduces PMS symptoms by 50%. Additional studies have since shown that replenishing the body’s vitamin D at the same time (which helps the body absorb calcium) reduces symptoms by 90-100%.