In general, sex drive gradually decreases as we age. Original research from the 1950s by Dr. Alfred Kinsey found that a man’s sexual peak was age 18, while a woman’s sexual peak tended to be in her mid-20s, with the downward slope from there varying from person to person.

Finally, at age 60, men typically had a higher sex drive than women. While Kinsey’s findings are still relevant today, we now know much more about what affects sex drive.

Although a handful of physiological mechanisms affect your libido, your thyroid function plays a major role in regulating sex drive – both up and down.

And thyroid issues are prevalent: 10% of women have a thyroid-related health issue, and by age 50 women are 10 times more likely to have a thyroid-related health issue than men. So you can chalk up your changes in sex drive to aging or you can learn about your thyroid health and how you can help maintain passion and romance in your life.

Thyroid 101

Your thyroid is a small butterfly-shaped gland in the front of your neck and is responsible for secreting two hormones:  thyroxine (T4) and triiodothyronine (T3). Thyroid stimulating hormone (TSH) is secreted by the pituitary gland and stimulates the thyroid’s production and release of T3 and T4.

Thus, the pituitary gland is essential for healthy thyroid function.

The thyroid hormones act on nearly every cell in the body, exerting numerous effects that influence metabolism, including carbohydrate, fat and protein metabolism, protein synthesis, bone metabolism, and neuronal connections.

Although sex drive tends to decrease with age, thyroid dysfunction that affects T3 and T4 levels can occur at any age. A lower level of these hormones is classified as hypothyroidism, whereas higher than normal levels is considered hyperthyroidism.

Both hypo- and hyperthyroidism are linked to sexual dysfunction in men and women:  erectile dysfunction for men and painful sexual intercourse for women. 

Both sexes can experience other issues too, including low libido. In recent years we have also developed a better understanding of the effects of hypothyroidism on female fertility and reproduction.

For example, hypothyroidism can decrease estrogen and testosterone levels in women of reproductive age.1 A low estrogen level is known to result in painful sex due to a lack of vaginal lubrication, and low testosterone can affect sexual desire and satisfaction; and they can both affect a woman’s ability to conceive. 

Thyroid dysfunction and sex drive prevalence

While this isn't one of the most well-researched topics, there are some interesting findings to help you understand how prevalent sexual issues relating to thyroid dysfunction really are. 

Males

In a study that looked at hyper- or hypothyroidism in 71 men, 56 of them (79%) had erectile dysfunction issues ranging from moderate to severe.2 In another study, the most prevalent sexual dysfunction symptoms associated with hyper- or hypothyroidism were hypoactive sexual desire, erectile dysfunction, premature ejaculation, and delayed ejaculation. This study showed that when therapies were implemented to normalize thyroid hormones the sexual issues resolved.3

Females

Research suggests about 46% of women who have a thyroid disorder (hyper, hypo, Hashimoto's) experience sexual dysfunction; 68% of women who have nodular goiter can also experience these issues. In these females, the most common issues reported were the lack of desire, arousal, lubrication, orgasm, and satisfaction.4 

Supporting your thyroid health

In addition to testing your thyroid levels to know your status, you should consider other diet and lifestyle habits so this important gland will maintain optimal function.

1. Try the Mediterranean Diet. The healthy fats from fish, nuts, and olive oil, a variety of vegetables, some whole grains and legumes, and moderate red wine consumption support whole-body health, decrease inflammation, and provide necessary vitamins and minerals (including iodine) to maintain optimal thyroid function and hormone balance.

If your diet is not so balanced, then consider supporting it with supplements that include selenium, magnesium, iron, copper, B vitamins, and vitamins A, E, and C.

2. Avoid toxins in the environment. Exposure to heavy metals, industrial chemicals, plastics, and pesticides can overtax your body, including your thyroid gland. Although everyone has a different tolerance, the best practice is to avoid and eliminate contact with these toxins when you can.

If you think you might have been exposed to excess levels of heavy metals (mercury, cadmium, or lead), then consider Thorne’s Heavy Metal Test.

3. Avoid stress and practice yoga. Stress can be a major factor in affecting your thyroid function. Practicing yoga or engaging in other relaxing activities, such as meditative stretching or low-intensity exercise, can help lower stress levels. Identify what’s causing your stress and incorporate healthy habits to minimize it.

Other factors affecting sex drive

Although thyroid abnormalities do affect sex drive, other issues can negatively or positively affect libido, either alone or in conjuction with thyroid issues.

4. Prescription medications – most notably anti-depressants – can lower sex drive. For example, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and tricyclic anti-depressants are known to have significant sexual side effects that range from reduced genital sensations to inability to achieve orgasm to erectile dysfunction.

5. Medical conditions – such as anxiety, depression, arthritis, diabetes, cancer, and sleep apnea all play a role in influencing hormone levels, energy levels, ability or desire to move around, and ultimately arousal. It's no surprise when your body is not in hormonal balance that you might not be in the mood.

6. Pregnancy – is a period when arousal can be enhanced. A pregnant woman has a larger volume of blood and extra blood flow around her vulva. After pregnancy, nursing, fatigue, or changes in perceived body image can dampen sex drive. This is also another time when hormones play a role.

7. Life events – both good and bad – can change your libido. Getting married, receiving a promotion at work, or finally taking a relaxing vacation can have a positive impact on your libido for days or even weeks; whereas, losing a job, stock market volatility, or selling a home can cause enough negative stress to impact your sex drive.

8. Lifestyle habits – like too much alcohol, too much exercise, or not getting enough sleep can all make you too tired for sex. On the flip side, not enough exercise or too much sleep can have the same effect.

A traveling work schedule or taking care of kids at home can increase your feelings of fatigue and reduce your sexual desire, too. It’s important to find the time and energy in your busy schedule to get proper exercise and sleep in order to get you in the mood.

9. Your daily diet – can affect the way you feel about yourself. A diet that consists of greasy, processed foods and extra sugars can cause weight gain that won’t have you feeling sexy between the sheets. On the other hand, a diet that supports the appropriate hormone balance (estrogen, testosterone, cortisol, thyroid hormones) can play an important role in supporting a healthy libido.

Eat plenty of nutrient-dense vegetables and colorful fruits (be careful of the sugar content) to obtain necessary vitamins and minerals. Also, including healthy fats in your diet (but not combined with high carbohydrates) can provide the precursors that produce sex hormones, which will also boost your libido. Which brings us back full circle to the Mediterranean Diet.


References

1.     Saran S, Gupta B, Philip R, et al. Effect of hypothyroidism on female reproductive hormones. Indian J Endocrinol Metab 2016;20(1):108-113.

2.     Krassas G, Tziomalos K, Papadopoulou F, et al. Erectile dysfunction in patients with hyper- and hypothyroidism: how common and should we treat? J Clin Endocrinol Metab 2008;93(5):1815-1819.

3.     Carani C, Isidori A, Granata A, et al. Multicenter study on the prevalence of sexual symptoms in male hypo- and hyperthyroid patients. J Clin Endocrinol Metab 2005;90(12):6472-6479.

4.     Pasquali D, Maiorino M, Renzullo A, et al. Female sexual dysfunction in women with thyroid disorders. J Endocrinol Invest 2013;36(9):729-733.