By LOUISE CARR, Associate Editor and Featured Columnist
It may surprise you, but men don’t own the hormone testosterone. Sure, when you Google "testosterone" you are more likely to have images of muscled men pop up. After all, testosterone is what gives men their sex drive, strength and, often, aggression.
But women also have the so-called “male hormone”– and testosterone levels affect women’s health, too.
Testosterone belongs to a set of hormones called androgens, and the ovaries produce both testosterone and estrogen. Women may not produce as much testosterone as men, but when levels fall it can affect your sex drive and your overall health. What can you expect if you have lower than average testosterone levels? What health dangers does having low testosterone present to women?
What Exactly Is Testosterone?
Testosterone is a hormone, a chemical substance that the body secretes which travels through bodily fluids to make something happen elsewhere in the body.
Hormones are like messengers, carrying information and instructions affecting health.
Testosterone, along with estrogen, is a sex hormone that affects reproduction, growth, and behavior. Both women and men make testosterone, although men have much higher levels than women.
What Are Normal Testosterone Levels for Women?
Normal testosterone levels in women vary. But experts say that adult women have a testosterone level in the region of 8-60 ng/dL, according to the Mayo Clinic. The University of Rochester Medical Center says normal testosterone levels for women are from 15 to 70 ng/dL.
In comparison, adult men have a range of 240-950 ng/dL, more than 3 times the levels normally found in women.
Testosterone levels, as with other hormone levels, vary throughout a woman’s life, and even throughout the day and month.
In your body, testosterone is made in short bursts and sent around the body in pulses, varying between day and night, and between one stage of the menstrual cycle to the next.
That’s why it is difficult to test women’s testosterone levels and to agree on a point where levels fall low enough to cause health problems.
What Happens If Your Testosterone Levels Fall?
Low levels of any hormone mean that the body is out of balance, which automatically creates health effects.
Low levels of testosterone in women cause issues like low libido, weight gain, fatigue, and may even affect fertility.
Should You Take Testosterone Replacement?
Women with low testosterone levels may feel that testosterone replacement therapy will help – but is it a good idea?
Studies show that testosterone replacement therapy can have beneficial effects on a variety of complaints caused by low levels of the hormone, such as sexual function and depression, but supplementation could also increase the risk of heart disease and liver disease.
Testosterone replacement therapy also comes with side effects such as acne, hair loss or growth, changes in the menstrual cycle, and a deeper voice.
We looked at the reasons why testosterone replacement therapy is sometimes recommended – health effects for women of too little testosterone in the body.
1. Low Testosterone Means Reduced Libido
Testosterone is an important factor in sexual function for both men and women. For women, the effects are less dramatic than for men, but the hormone does still play a part and low levels of testosterone are linked with low libido and sexual performance problems.
But all of us are becoming more aware of the importance of testosterone. A 2001 research study from the Jean Hailes Foundation in Australia found that there is an increasing awareness of the significant action of testosterone on women and particularly on sexuality.
A 2005 study from Cedars-Sinai Medical Center, LA shows that testosterone therapy could be effective for women with low testosterone levels suffering from lack of sexual interest, desire, and satisfaction.
And a 2014 study from Monash University, Melbourne, in Australia demonstrates that testosterone improves libido in women suffering this side effect though taking antidepressants.
However, since testosterone replacement therapy also causes side effects, it is not universally recommended for treating the complex issue of female sexual function.
Doctors carefully monitor the dose of the hormone to ensure results with minimal side effects.
2. Low Testosterone Affects Your Ability to Build Muscle
While lack of muscle may be more associated with men, it also affects women .
Low levels of testosterone can stop the body effectively building muscle and may even cause you to lose muscle mass.
For example, a 2015 study from Kochi University, Japan looked at testosterone levels and muscle mass in 430 women aged between 40 and 79, and discovered that low testosterone was linked to muscle loss in the arms and legs over time.
3. Low Testosterone Levels Make it Difficult to Lose Weight
One of the functions of testosterone is the regulation of the placement of muscle and fat on the body.
When you have low testosterone you are at risk of having more fat, particularly around the middle.
In studies looking at men like a 2013 study from the State University of New York at Buffalo, obesity and low testosterone are linked, although it is hard to be certain that low testosterone causes weight problems and not the other way around.
4. Your Depression Could be Caused by Low Testosterone
Depression and mood disorders are unlikely to be solely caused by testosterone.
But research shows that low levels of testosterone are linked to depression.
In a 2012 study from Leiden University Medical Center, The Netherlands, women aged 25 to 46 with low testosterone levels were more likely to be depressed, or to have an anxiety disorder.
In addition, a 2009 study by Massachusetts General Hospital, Boston shows that low-dose testosterone improves depression severity in women with major depressive disorder. The study looked at nine women.
5. Low Testosterone Puts You at Increased Risk of Osteoporosis?
Osteoporosis, the condition that causes weak bones, is more likely to be caused by lack of estrogen in women, but the condition is also affected by testosterone levels.
When testosterone is out of balance, estrogen replacement may not be so effective for preventing osteoporosis.
A 1999 study from the University of Pennsylvania School of Medicine shows that testosterone treatment in men over 65 years of age improved bone density when testosterone levels were previously low.
6. Low Testosterone Levels are Linked to Fertility Problems in Women
Can male sex hormones improve a woman’s fertility? Experts believe so.
A recent 2016 study from The Center for Human Reproduction in New York says that testosterone is essential for the growth and maturation of small follicles, the structures that go on to contain and release eggs.
The study looked at data from 355 infertile women and suggests that testosterone supplementation can help women who have diminished ovarian reserves and produce few or no follicles during IVF.
We need more studies in this area but the indication is clear. For some women, eating foods such as oysters that boost testosterone may in fact help you conceive a baby more easily.
7. Better Balanced Testosterone Helps Pain Management
Taking birth control pills prevents pregnancies but that also have a side effect --they may increase the amount of pain you feel. According to a 2015 study from the University of São Paulo in Brazil, women taking birth control pills (which lower levels of testosterone compared to estrogen) have less ability to manage their pain response.
The study, looking at 89 non-users of contraception and 188 users of hormonal contraception, implies that testosterone is an important factor in the pain management response.