A man can have a normal Testosterone level and feel terrible, if he has a lot of Estrogen.
I look at the metabolic activity of T in individuals as an interplay between blood levels of T and the receptor sites that receive the hormone and activate the cells to do the job the cells are genetically programed to do. For example a man can have a total T level of 800 (400-1500 normal) and a Free T of 130 (nl=129-350), which is completely normal, but if he has insensitive receptor sites and he also has a lot of estrogen circulating, then his receptors are filled with E2 estrogen and the man does not feel his testosterone, and he is symptomatically hypo-testosterone. This is one of the mistakes that doctors make when they just look at the total or T and Free T and don’t consider the estrogen level and the symptomatology of the patient. A man can have a normal T and Free T and feel terrible, if he has a lot of E2.
Generally, E2 and E1 in the blood will also decrease the free T but you must consider that it is also blocking the T receptors from activity.
A Word About Genetics and The T Receptor
Your T receptors are genetically programmed to be sensitive to T or insensitive to T. This means that If you are sensitive to T you do not need as much T in your blood to feel normal. If you are insensitive to T, you require a higher blood level of T to feel normal. No man or woman is the same, however extensive research has been done on the T receptor and it was found that the genes that determine sensitivity are more common in people from near the equator, and as you go toward the northern latitudes people become less sensitive. T receptors determine a man’s risk of prostate cancer in his lifetime. If he has sensitive receptors, he is more likely to get prostate cancer than if he is insensitive. Ergo, African heritage carries with it a high risk of prostate cancer, a sensitivity to T, and these men don’t need as much T to feel normal. Women carry the same genetics, but don’t have the fear of prostate cancer, but still need less T in the blood stream to feel normal.
T Receptor sites accept Estrogens, E1 and E2 as well as T. In fact, Estrogens and T compete for attaching to the T receptors, and estrogen is three times as “sticky” as testosterone. This makes the level of estrogens very important to both men and women. This competition explains why women can have total T levels as high as a man, yet if her estrogen is present at normal levels then the free T levels are very low compared to what it would be in a man with low E2 levels.
T Production Time
T is produced throughout life in men, but only for about 30-40 years in women, and from puberty until death in men. This makes sense in terms of anthropological study because men were created to produce children with many women over many years because women had a 50% death in childbirth rate in the past. In addition, Men actually need T to get an erection and have sex, but women can have sex without testosterone, however they may not like it! This longer T exposure time in men protects him from diseases that occur secondary to low T: autoimmune diseases, diseases from poor immune status, diabetes and loss of both muscle mass and strength. T keeps men from getting osteoporosis and frailty, which is a common disease in women as they get older.
Estrogen Levels in Women vs Men affect Testosterone Effects
The level of estrogen doesn’t determine the production of T from the ovary or testicle, it acts in the blood stream after T production is finished. Estrogens go to the liver of both men and women and stimulates the production of a protein called Sex Hormone Binding Globulin (SHBG). This protein attaches to testosterone and inactivates it. The higher the estrogen, the higher the SHBG, the lower the activity of testosterone! The difference between young men and women is that young women have moderately high E2 and E1, and young men have very little. This explains the vast difference between the active levels of T (Free T) between the sexes. As women and men get older estrogen dominance becomes a problem that binds up the testosterone and free T decreases. Men make more E1 and E2 as they age and slowly decrease their total T production, which is a double whammy and their effective levels of free T plummet after age 50, even though they continue to produce it. Maintaining low normal Estrogen levels is important to both men and women.
Conclusion T differences between Men and Women
When doctors just look at total T level or even Free T levels and do not look at the symptoms of low T they aren’t even scratching the surface of what is wrong and how to treat a man or woman who has low T symptoms.
I often have female patients come in and say, “My PCP told me that you made my testosterone level as high as a man’s, that I’m going to become a man!” Hopefully now you can see why that is a very uninformed statement from the doctor. Women may have a high total blood level, but they will have a very small % that is active and because they have so much estrogen to compete with T at the receptor sites, they aren’t even in the same universe of T levels or T effects on their metabolism as men!
Understanding the difference is key to talking to your doctor and understanding your T hormonal treatment. In the hormonal universe, men are from Mars and women are from Venus!
This Health cast was written and presented by Dr. Kathy Maupin, M.D., Bio-identical Hormone Replacement Expert and Author, with Brett Newcomb, MA., LPC., Family Counselor, Presenter and Author. www.BioBalanceHealth.com.