It is well known that aging results in the shrinkage of the thymus gland, along with a reduction in the secretion of thymic hormones and T-cells, all of which are essential for maintaining youthful immune synchronization. 

     A study published in the journal Immnological Reviews (1997, Vol. 160) showed that excess estrogen may be the primary sex hormone responsible for age-induced thymic involution (shrinkage) and associated immune dysfunction.  The name of this extensive study was “Thymic Aging and T-Cell Regeneration,” and it suggested that hormone modulation was one way of accomplishing thymic regeneration.

     A chapter from the 1998 textbook Principles and Practices of Geriatric Medicine entitled “Immunity and Aging” also discussed the role sex steroid hormones play in thymic involution.

     These studies suggest that restoring youthful sex hormone profiles could assist in protecting against immune impairment caused by the shrinking thymus gland.

     There are also two studies that conclusively show that men with MPB have elevated levels of cortisol, estrogen, and androstendione.