The author evaluated the effects of DHEA (Dehydroepiandrosterone) on the amount of telomeres of normal cells and cancer cells and found the following: Contrary to the literature, which often recommended 25-50 mg of DHEA daily for the average adult human being, the author found that, depending on the individual, the maximum increase of normal cell telomere was obtained by a single optimal dose of 1.25-12.5 mg. This was examined in 50 people, both males and females, between the ages of 20-80 years old. When one optimal dose was given to each individual, the average telomere amount in normal tissues, measured in Bi-Digital O-Ring Test units, often increased from anywhere between 25-300 ng to between 500-530 ng. Cancer cell telomere reduced from higher than 1100 ng to less than 1 yg (=10(-24) g) with equally significant normalization of abnormal cancer parameters (such as Integrin alpha5beta1, Oncogen C-fosAb2, Acetylcholine, etc.). Circulatory improvement and an increase in grasping force of up to 25% were also detected, along with the changing of a few white hairs to black hairs. The beneficial effects of one optimal dose of DHEA generally lasted between 1 to 4 months, though in some individuals it lasted for a much shorter period of time due to a number of negative factors such as excessive stress/work, excessive exposure to low temperatures and toxic substances, or use of common pain medicines. On the other hand, if a patient took an excessive dose of DHEA, the amount of normal cell telomere decreased, while there was an increase in cancer cell telomere. It was found that those who took an overdose of 25-50 mg daily for more than 3 months had a high incidence of cancer of the prostate gland, breast, colon, lung, and stomach. Also, when the average normal cell telomere levels were less than 110 ng, compared with a normal value of 120-130 ng, and when DHEA in different parts of the body was also extremely low (less than 1-2 ng), one could suspect the possible presence of a malignant tumor somewhere in the body. When normal cell telomere was less than 110 ng, most individuals felt very weary with marked tiredness in the eyes, and grasping force was often reduced.