Is There a Link Between Low Testosterone and Dementia?

On: February 6, 2020
Dementia, low testosterone, trt

It’s common knowledge that as we age our testosterone levels lower. However, a recent study showed that a large sample of American men’s testosterone levels was dropping by as much as 1% each year.

And this sudden drop is something new. That same study showed that a 65-year-old man in 1987 had 17% more testosterone than a man the same age in 2004.

That’s worrisome for many reasons, especially since lower levels of testosterone means health issues such as lowered energy levels along with decreased libido and muscle mass. A decrease in testosterone also has negative effects on our cognitive health.

Testosterone helps with memory, attention, and spatial reasoning. It’s also been linked to depression.

But does that mean there’s a link to dementia? Keep reading to learn about the possible connection between low testosterone and dementia.

What is Testosterone?

Testosterone is the primary sex hormone in men. It regulates things such as fat distribution, red blood cell production, muscle mass, and fertility in men.

It’s during adolescence that testosterone production levels are at their highest. By late teens or early 20s, production levels peak.

After age 30, testosterone levels can naturally drop by 1% annually.

Testosterone in Women

In women, testosterone along with estrogen helps with the growth and maintenance of bone mass and female reproductive tissue. These two hormones also affect behavior.

Women produce small amounts of testosterone in their adrenal glands and ovaries.

When testosterone levels drop below healthy levels, it can cause health issues.

Why Testosterone Levels are Dropping so Rapidly

Studies are showing that the sudden dramatic drop in testosterone levels may have something to do with pollution. A study found that a new group of chemicals act as anti-androgens.

The anti-androgens inhibit the function of testosterone. Anti-androgens can be found in medicines, including cancer treatments, pharmaceutical treatments, and even agricultural pesticides.

Anti-Androgens are Wreaking Havoc on our Water Systems

As the anti-androgens find their way into our water systems through our sewer treatment works, they may be the reason why there’s a sudden feminizing effect in male fish. That’s because these chemicals mimic estrogen.

The pollution then causes reproductive problems because it reduces how well fish can breed. Sometimes male fish can change gender.

The Effects of Testosterone on the Body

Testosterone in men does a lot for their bodies.

As testosterone levels increase during puberty, males see a growth in the penis, pubic hair, and testicles. Their voice also deepens, they grow muscles and more body hair.


An increase in sexual desire also occurs during puberty. However, as those levels decline, men may lose their desire for sex and even cause erectile dysfunction.

Also, to produce enough sperm, men need a steady supply of testosterone. When levels of testosterone drop, it becomes harder for men to conceive with their partner.

Body Hair

Testosterone helps with hair production, including around the genitals, on the face, and in the armpits. Testosterone can also increase hair growth on the chest, arms, and legs.

As testosterone levels decrease, men may notice a loss in body hair.

The Endocrine System

Hormones are manufactured by glands in the body’s endocrine system. It’s the hypothalamus, which is located in the brain that tells the pituitary gland how much our body needs.

The pituitary gland then sends along that message to the testicles in men. While most testosterone is produced in the testicles, the adrenal glands, located just above the kidneys, also produce small amounts.

The Central Nervous System

Testosterone affects certain behaviors such as aggression and dominance. Those with higher levels of testosterone are more likely to be more competitive. Even taking part in competitive activities can cause higher or lower testosterone levels in a man.

They’re also more likely to have higher self-esteem levels.

Those with lower levels of testosterone may feel a lack of motivation along with lower self-esteem.

Lower levels are also attributed to a lack of energy and problems sleeping.

However, testosterone isn’t the only factor that has an influence on personality traits. There are other environmental and biological factors involved.

The Circulatory System

It’s through a blood test that you can find out what your testosterone levels are. That’s because testosterone travels through the bloodstream around the body.

That’s how testosterone helps the bone marrow to produce red blood cells. However, whether testosterone positively affects the heart, cholesterol, and blood pressure is still unknown.

Muscle, Bone, and Fat

While there are many factors that contribute to the development of muscle bulk and strength, testosterone helps. In fact, testosterone encourages tissue growth by increasing neurotransmitters.

Men with low levels of testosterone usually have a lower bone density, making them more prone to bone breaks and fractures. Low testosterone can also lead to an increase in body fat, as it plays a role in fat metabolism.

Low Testosterone Symptoms

There are some common symptoms that both men and women have when their testosterone levels drop. Other symptoms are unique to that gender.

Low Testosterone Symptoms in Men

Here are some common symptoms men experience when their testosterone levels drop:

  • Difficulties achieving erections
  • Lower sex drive
  • Hair loss
  • Low semen levels
  • Increase in body fat
  • Fatigue
  • Loss of muscle mass
  • Mood changes
  • A decrease in bone mass
  • Low blood counts
  • Smaller testicle size

Since both testosterone and cognitive functions decline as we age, doctors theorize that lower testosterone levels contribute to affected memory.

Low Testosterone Symptoms in Women

Here are some common symptoms women experience when their testosterone levels drop:

  • Fatigue
  • Problems sleeping
  • Muscle weakness
  • Sluggishness
  • Reduced sex drive
  • Fertility issues
  • Weight gain
  • Vaginal dryness
  • Loss of bone density
  • Irregular menstrual cycles

Women also experience a decreased level of sexual satisfaction. If a woman is experiencing these symptoms, she must visit her physician to rule out other causes such as depression, thyroid disease, or menopause.

Low Testosterone and Dementia

Scientists are increasingly coming to believe that low testosterone levels are associated with blood vessel (vascular) problems. They also discover that low testosterone is linked to heart disease and stroke, both of which are risk factors for dementia.

While they need more studies, scientists also believe there is a connection showing that testosterone protects the brain, especially areas of the brain prone to dementia.

What the Studies Show

In a study performed at Siloam Hospital in Lippo Karawaci, Tangerang, Indonesia, when test subjects were administered testosterone, they showed an improvement in cognition over those taking the placebo. That same study showed that even if the subject stopped hormonal manipulation, they did not return to their baseline levels but continued to change in the same direction.

Studies also show that low levels of testosterone are associated with a higher risk of dementia for elderly men aged 80 or older. It also showed a higher risk of dementia in men who had higher levels of education.

Findings from a study at Wayne State University

In 2004 at Wayne State University, researchers examined testosterone levels in men in an aging study. Researchers discovered that every 50% increase in free testosterone in these men was directly associated with a 36% decrease in their risk of developing Alzheimer’s.

It was also found that those men in the study who developed Alzheimer’s disease had only around half of the free testosterone in their bloodstreams as those men who did not develop Alzheimer’s.

Low Testosterone and Dementia in Women

Another study by researchers from Monash University in Australia involved 90 healthy postmenopausal women. Researchers had one group use a testosterone gel to apply to the upper arm every day.

The other group was given a placebo gel. After 26 weeks researchers tested the women’s cognitive skills again.

The results showed that those who used the testosterone gel had higher testosterone levels but were still within the typical female range. It also showed that women using testosterone gel showed significant improvement in memory and verbal learning.

Ways to Restore Your Cognitive Health

Fortunately, there are cognitive health solutions that can help ward off dementia and Alzheimer’s. Most solutions are fairly easy and won’t cost you a dime such as:

  • Eat a healthy diet
  • Get more exercise
  • Get a good night’s sleep
  • Take up a new hobby
  • Solve new puzzles
  • Play games
  • Visit new places such as museums and historical sites
  • Attend workshops

Staying active and healthy are the best ways to reduce your chances of declining cognitive health.

Help Save the Planet

However, you should also avoid drinking from plastic containers so you don’t ingest harmful chemicals.

You can also get political and help to change current environmental laws. There is a mountain of proof that the pollution humans have directly caused is causing numerous health issues above and beyond declining testosterone levels.

Another option is testosterone replacement therapy (TRT).

What Testosterone Replacement Therapy Is

Testosterone replacement therapy comes in several forms. TRT helps restore normal levels of testosterone.

However, it doesn’t come without a few side effects that every candidate should know:

  • Oily skin
  • Acne
  • Lower sperm counts
  • Infertility
  • Shrinking testicles
  • Larger breasts

Some people may not be good candidates because of ongoing health issues.

Always talk to your doctor first and share with him or her your current medical condition(s) and age to ensure you’re a good candidate for TRT.

The Benefits of TRT

Thankfully, there are myriad benefits to TRT, such as

  • Increased alertness
  • Feeling more energetic
  • Increase in sexual function

Many patients also see an increase in their mental sharpness.

The Various Ways to Receive TRT

There is more than one way to receive TRT. Each way comes with its own set of pros and cons.


Patches are easy to apply on the skin. But you may need to apply more than once each day and it can cause skin rashes.

Buccal Patch

With this patch, you place it on your upper gum twice daily.

While these patches are convenient, they can also cause gum disease and/or irritation.


With the gel, you rub it into your skin daily. While they are convenient to use, after you’ve applied it, you need to avoid anyone coming into contact with the treated area for several hours after application.

Anyone (or a pet) who comes into contact with the gel could get testosterone into their own system. However, there is now a nasal gel that can eliminate the risk of contact.


With injections, you receive one anywhere between two and 10 weeks apart. And compared to other treatments, they’re less expensive.

Unfortunately, you may get what you pay for as injections aren’t known for providing steady benefits. Testosterone levels go back down in between doses.

Subcutaneous Pellets

With subcutaneous pellets, your doctor inserts these under your skin every three to six months, depending on your testosterone levels and whether you’re a male or female.

While they’re convenient once inserted, they require minor surgery for each dose.

What Happens After You Receive TRT

After you receive your first TRT treatment, your doctor will measure your testosterone levels. Usually, this happens at the three- and six-month mark.

You’ll then be tested once a year to ensure your levels are where they should be. If they are, you’ll stay on your current dose.

If not, your doctor will adjust accordingly.

TRT Is Not a Cure

It is important to note that TRT doesn’t cure low testosterone.

If you stop treatment, your testosterone levels may drop back down and your symptoms can return. If you commit, you must do this for the rest of your life to enjoy the benefits.

See if Your Insurance Covers TRT

If your cognitive health isn’t what it used to be, it may be due to lowered testosterone levels. Fortunately, with TRT there is help available.

But many people worry about the cost. Thankfully, some insurance companies cover TRT. Check to see if your insurance company will help you pay for testosterone replacement therapy.

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