In her book, Eve’s Rib: The New Science of Gender-Specific Medicine Marianne J. Legato M.D says, “Everywhere we look, the two sexes are startlingly and unexpectedly different not only in their internal function but in the way they experience illness.” To begin with there are 10 trillion cells in the human body and every one of them is sex specific. The poet, Robert Bly, glimpsed this scientific truth when he wrote that boys need to be in the company of older men “in order to hear the sound that male cells sing.”
Until recently scientists believed that our genomes were 99.9% identical from one person to the next. “It turns out that this assertion is correct,” says David C. Page, M.D., professor of biology at the Massachusetts Institute of Technology (MIT), “as long as the two individuals being compared are both men. It’s also correct if the two individuals being compared are both women.” New research from Dr. Page’s lab shows that the genetic difference between a man and a woman are 15 times greater than the genetic difference between two men or between two women.
One of the most significant differences is in our levels of the hormone testosterone. Testosterone is often called the “male” hormone. However, both men and women produce this hormone. Did you know?
- Men have 20 to 40 times more testosterone (T) than do women.
This is one reason why our sex drives are so different. Men don’t think about sex all the time as some people believe, but we do think about sex, generally, more than women.
- Testosterone is responsible for the sex drive in both men and women.
When our sex drive begins to diminish as we age, the problem may be low T in men and women. Many women, and men, don’t realize that testosterone is important in keeping a woman’s sexual desire up.
- Testosterone can be converted to estrogen, but not the other way around.
One of the main reasons men suffer from low T is that significant amounts of T are being converted to estrogen (not a good thing). The main cause turns out to be increased body fat. So, another good reason to lose weight, guys, is to keep your sex life alive and well.
- Testosterone fluctuates daily, seasonally, and drops when we hit menopause (in women) and andropause (in men).
When I wrote my books, Male Menopause and Surviving Male Menopause: A Guide for Women and Men, many people laughed at the idea that men’s emotions fluctuated with their hormonal cycles. Now we know that men are as “hormonal” as women and our hormonal cycles have a significant impact on our love lives.
- Men become more “esty” as we age, while women become more “testy.”
Although both testosterone and estrogen drop as we age, for men our testosterone drops more significantly and we have a higher ratio of estrogen to testosterone. As a result, we become more “esty,” softer, gentler, and more emotional. For women, the opposite is true. As they age, their testosterone is more dominant and they become more “testy,” which makes them more assertive and aggressive.
- The normal range of testosterone varies greatly in both men and women.
In men, normal T levels can vary between 300 and 1200 ng/dl. In women, the range may vary between 15 and 70 ng/dl. As a result, it’s difficult to determine if someone is too low and might be a candidate for testosterone supplementation. For instance, if a man had levels of 400 when he was 20 years old and 350 when he was 50 years old, he might test normal and have few symptoms of low sexual desire. However, if he was 1200 when he was 20 and 350 when he was 50 years old, he would also test as normal, but might have significant symptoms. So, it’s good to have your hormonal levels tested when you are young as well as when you are older.
- High testosterone men are similar in many ways to high testosterone women.
Men and women at the higher end of the testosterone scale will be more aggressive, have more sexual partners, masturbate more often, and have more affairs, than men and women who are at the lower end of the scale. Research by James McBride Dabbs and Mary Godwin Dabbs, authors of Heroes, Rogues, and Lovers: Testosterone and Behavior, found that “High testosterone people seem to be unhappy when they are alone and happy when they are with people. Low-testosterone people seem to be less compulsively social.”
- Different professions seem to attract men and women with different T levels.
Dr. Dabbs and his team measured the testosterone levels of physicians, fire fighters, football players, salesmen, professors, ministers, and actors. They differed in the testosterone levels, with actors having the highest T scores and ministers the lowest: Actors, fire fighters, salesmen, football players, professors, and ministers. Are you in a higher T or lower T profession?
- Higher or lower testosterone levels are part of our evolutionary history and are important in dating, mating, and child-rearing.
Higher testosterone may be important in securing a mate, but lower testosterone may be better for being a good parent and caregiver. Many of us are drawn to high T people for excitement and sex, but lower T people may make the best spouses. Remember, high T men and women have more affairs and get into more fights. Married men are lower in testosterone than single men and testosterone levels drop when men get married and go up when they get divorced.
Dr. Dabbs found that men have lower levels of testosterone immediately after they become fathers. “Perhaps these hormonal changes set them up for the gentler activities of parenthood,” Dr. Dabbs concludes. So, the important thing to remember is that our hormone levels change and knowing ourselves can help us have more joyful and sexually fulfilling lives.
- Knowing your natural testosterone levels and accepting your own unique personality is important for long-term happiness.
Dr. Dabbs found that there are actually two kinds of people who differ in their normal levels of testosterone. “Frank Sinatra sang, ‘I did it my way,’ and the Beatles sang, ‘I get by with a little help from my friends,’” Dr. Dabbs reminds us. “These are the ways in which high- and low-testosterone people approach the world. Sinatra’s song is the self-congratulatory, high testosterone way. They are opposing strategies–one based on dominance and the other on cooperation.
When I think of higher T and lower T people, I often think of the Rolling Stones and the Beatles. They started at about the same time, dominated the music world, and will leave a lasting legacy. In contrasting the two groups, writer Tom Wolfe said, “The Beatles want to hold your hand. But the Stones want to burn your town.” Can you guess which one might be the higher-T group?
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This article originally appeared on Jed’s blog.
