What Testosterone Does For The Body

Clock 13 mins
31st Mar 2021
By: Project Alpha Team

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Testosterone is the main sex hormone and anabolic steroid in men. It plays a crucial role in the development of men’s reproductive tissues, such as the prostate and testes.

It is also responsible for boosting secondary sexual characteristics like increased bone mass and muscles and the growth of body hair.

Testosterone is also linked to sex drive and plays a significant role in the production of sperms. It also affects how men store fat in the body as well as the production of red blood cells.

The testosterone levels of a man have also been found to affect a man’s mood.


Low Testosterone

Researchers are beginning to unlock more mysteries of how low testosterone levels are related to a man’s health.

Recent research has concluded that low testosterone has links to metabolic syndrome, diabetes and obesity.

While low testosterone is not the definitive cause of these health problems and testosterone replacement therapy is not the cure, there are associations between low testosterone and a range of health issues.

Also referred to as simply low T levels, low levels of testosterone have been found to produce a wide range of symptoms in men. These symptoms include the following:

  • Less energy
  • Decreased sex drive
  • Erectile dysfunction
  • Difficulty concentrating
  • Body and facial hair loss
  • Low self-esteem
  • Moodiness
  • Weight gain
  • Thinner bones
  • Decreased muscle mass
  • Hot flashes
  • Increased body fat
  • Feelings of depression

Researchers have noted general links between low testosterone levels and a range of medical conditions. A study concluded that in every 2,100 men over the age of 45, the odds of having low testosterone levels were:

  • 1.8 times more for men with high blood pressure
  • 2.1 times more for men with diabetes
  • 2.4 times higher for men with obesity

Experts have, however, suggested that low testosterone may not be the cause of these health conditions. It might actually be caused by these health conditions. They believe that men with certain medical problems may develop low testosterone over time.

  • Diabetes

There is a known link between low testosterone levels and diabetes. Men that have diabetes are more likely to have low testosterone levels. On the other hand, men that have low testosterone are more likely to develop diabetes later.

Testosterone helps your body tissues to take more blood sugar in response to insulin. Men that have low testosterone often have insulin resistance. They have to produce more insulin in order to maintain normal blood sugar levels.

Statistics have shown that at least half of the men with diabetes also have low testosterone levels. Scientists are, however, not sure if it is low testosterone that causes diabetes or diabetes that causes low testosterone. While it is not a cure for diabetes, TRT may offer some help to persons with diabetes.

  • Obesity

There is a tight link between low testosterone and obesity. Researchers have found that persons with obesity are more likely to develop low testosterone. Men that have extremely low testosterone levels are more likely to become obese.

Just like with diabetes, it is not clear if obesity is what causes low testosterone or the other way round.

Testosterone is metabolized by fat cells into estrogen. This leads to lowered testosterone levels. Obesity has also been found to reduce levels of SHBG (sex hormone binding globulin).

SHBG is a protein that carries testosterone into the blood—having less SHBG results in less free testosterone. As a result of this, losing weight by exercising will increase the levels of testosterone.

  • Metabolic syndrome

Metabolic syndrome is a condition that includes the presence of high blood pressure, abnormal cholesterol levels, high blood sugar and waistline obesity. This condition increases a person’s risk for strokes and heart attacks.

Researchers have found that men that have low levels of testosterone are more likely to have metabolic syndrome.

In some studies, testosterone replacement therapy improved blood sugar levels and obesity in men with low levels of testosterone. However, due to the risk that testosterone therapy poses, it is not recommended for treating metabolic syndrome.

A blood test may be required to determine if you are a good fit for the therapy.

  • Heart disease

Testosterone has varying effects on arteries. Experts believe testosterone is one of the contributors of high rates of high blood pressure and heart disease that affects younger men.

With this in mind, high levels of testosterone may be harmful to both your blood pressure and heart.

On the other hand, low levels of testosterone are linked to obesity, diabetes and insulin resistance.

These problems elevate cardiovascular risks. It has also been concluded that men with low testosterone and diabetes have higher rates of atherosclerosis (hardening of the arteries).

Some level of testosterone may be required for healthy arteries. This is because it is usually converted into estrogen, which in turn protects the arteries from getting damaged.

A study of 4,000 men over the age of 70 concluded that participants with the lowest levels of testosterone were more than twice likely to be depressed.

The link was still there even after allowing for general health, age, obesity and a range of other variables.

Low libido and erectile dysfunction are the most common symptoms of low testosterone. While in most older men, erectile dysfunction is caused by atherosclerosis, low testosterone is also the cause.

This is because testosterone stimulates penile tissues to produce nitric oxide. This triggers a variety of reactions that lead to an erection.

If you have low levels of testosterone, you may not be able to get or maintain an erection.

It is, however, good to note that erectile dysfunction may be caused by several other factors. These factors include:

  • Thyroid-related issues
  • Smoking
  • Alcohol consumption
  • Anxiety or stress
  • High cholesterol
  • High blood pressure
  • Diabetes

It is also good to note that testosterone is the hormone that stimulates semen production.

Semen is the fluid that makes up the majority of a male ejaculate. It is the fluid that helps sperms to move towards the egg.

Reduced semen levels may indicate low levels of testosterone. This can also lead to fertility problems.

While all the above health problems have been linked to low testosterone, the question still remains if low testosterone is what causes these problems or the health problems are what cause the problem.

Researchers are yet to answer this question. If you plan on taking testosterone replacement therapy, this is a decision you should make with your doctor. A blood test will be taken to determine your suitability.

The doctor will also consider the condition that is being treated to determine if TRT is the way to go. In most cases, testosterone therapy is recommended for persons with low testosterone for the treatment of low libido/ erectile dysfunction.


What Causes Low Testosterone Levels

While the natural levels of testosterone taper as one ages, there are factors that cause the hormone levels to drop.

Low testosterone levels may be caused by cancer treatments such as radiation and chemotherapy or injury to the testicles. There are also chronic health conditions and stress that can cause low testosterone. Some of these conditions include:

  • AIDS
  • Alcoholism
  • Kidney disease
  • Cirrhosis of the liver

Testosterone levels also decline steadily in women. Low T can lead to a range of symptoms, including:

  • Depression
  • Low libido
  • Poor concentration
  • Reduced bone strength

The removal of the ovaries can cause low testosterone in women. The low levels may also be caused by disease of the hypothalamus, adrenal glands and pituitary.

Testosterone replacement therapy may be prescribed for women that have low testosterone levels. It is, however, unclear if the therapy can improve cognitive function or sexual function among postmenopausal women.


Testing Testosterone

There is a wide range of healthy or normal levels of testosterone that circulate in the bloodstream. A blood test can help determine your testosterone levels.

According to the University of Rochester Medical Center, the normal testosterone levels for adult male range from 280 to 1,100 nanograms per deciliter (ng/dL).

For adult females, the normal range is from 15 to 70 nanograms per deciliter. These ranges can change from one lab to another. It is always recommended to consult your doctor regarding the results.

If the testosterone levels of an adult male are below 300ng/dL, the doctor may do some work-up to determine the cause of low T.

In some cases, low levels of testosterone may be caused by pituitary gland problems. The pituitary gland is what produces the hormone that signals the testicles to produce more testosterone.

Having low T in an adult male may mean that the pituitary gland is not working properly. A teen with low levels of testosterone may be due to delayed puberty.

Testosterone levels that are moderately elevated in men can cause a few noticeable symptoms, e.g. boys may start puberty earlier. Women that have high testosterone may develop some masculine features.

Adrenal gland disorder may cause abnormally high levels of testosterone. Cancer of the testes has also been found to cause elevated levels of testosterone.

It is normal to have high levels of testosterone in less serious conditions. For example, congenital adrenal hyperplasia can cause high levels of testosterone. This condition can affect both men and women.

However, if your levels of testosterone are extremely high, the doctor may order additional tests to determine the cause. For this reason, you should not ignore a blood test if you suspect you have low or extremely high testosterone levels.

Common causes of low testosterone include the following:

  • Ageing
  • Injury or infection of the testes
  • Chemotherapy
  • Metabolic disorders like hemochromatosis
  • Tumours or dysfunction of the pituitary gland
  • Alcohol abuse
  • Cirrhosis of the liver
  • Medications which include hormones used to treat prostate cancer, steroids and opioids
  • Inflammatory conditions like sarcoidosis (a condition that causes the inflammation of organs)
  • Klinefelter syndrome
  • Kallman syndrome
  • High levels of the milk-producing hormone prolactin
  • Head injury
  • Pubertal delay
  • Severe primary hypothyroidism
  • Previous abuse of anabolic steroids
  • Obstructive sleep apnea
  • Congenital defect
  • Uncontrolled type 2 diabetes mellitus
  • Extreme weight loss or obesity
  • Estrogen excess due to environmental or external sources

Changes that occur with low testosterone levels include:

  • Infertility
  • Increased body fat
  • Decreased body hair
  • Decreased haemoglobin and mild anaemia
  • Breast development in men
  • Thinning of the bones


How is low testosterone diagnosed?

A blood test is needed to diagnose low testosterone. This is done to measure the amount of testosterone in the blood. Several measurements may be required to determine if a person has low testosterone levels.

This is because testosterone levels change throughout the day. A person generally has the highest levels of testosterone in the early morning, typically at around 8 am. For this reason, most doctors will prefer to get your blood tested in the early mornings.


How is low T treated?

Testosterone replacement therapy is used to treat low testosterone. This treatment is given in various ways:

  • Intramuscular injections: This is done every 10 to 14 days.
  • Testosterone patches: These have to be used daily. They are applied to various parts of the body, including arms, back, abdomen and buttocks.
  • Testosterone gels: This is applied every day to clean dry skin on the arm and upper back. Care has to be taken when using the gel to ensure it is not transferred by accident to another person.
  • Pellets: These are implanted under the skin every two months.
  • Oral testosterone: While this is available, it is not approved for use in most places.


What are the advantages of testosterone replacement therapy?

There are many potential benefits that come with TRT. They include the following:

  • In young boys, TRT can be used to avoid the issue of delayed puberty
  • Improve sexual function
  • Improve mood and sense of well-being
  • Improved muscle strength
  • Improved physical performance
  • Increased bone density and protection against osteoporosis
  • Loss of fat


Does TRT have side effects?

Yes. The side effects include the following:

  • Oily skin or acne
  • Breast tenderness or enlargement
  • Swelling in the ankles as a result of mild fluid retention
  • Worsened sleep apnea: This is a disorder that leads to frequent night-time awakenings and daytime sleepiness
  • Prostate stimulation that causes urination symptoms like difficulty urinating
  • Skin irritation
  • Smaller testicles

There are also laboratory abnormalities that may occur following testosterone replacement. They include:

  • Increased prostate-specific antigen
  • Decreased sperm count leading to infertility
  • Increased red blood cell count

Due to these side effects, it is required that you get regular follow-up appointments with a doctor if you are taking testosterone replacement therapy. Prior to getting started with testosterone replacement, it is imperative that you discuss the potential benefits and risks of the treatment.

Prostate risk and prostate monitoring have also to be evaluated. You and your doctor will decide the right way forward in regards to prostate cancer monitoring.

If you choose regular monitoring, a clinician will assess your prostate cancer risk before treatment starts. Assessments will then be done every 3 to 12 months after TRT starts.

  • Prostate-specific antigen levels have to be checked 3, 6 and 12 months in the first year. After that, the levels should be checked every 12 months.
  • Digital rectal examination of the prostate has to be done 3 to 6 months, and one year after therapy starts. The examination will then be done every 12 months. This examination is required even for men that are not using testosterone replacement therapy. After the age of 50, an age-related prostate cancer screening will be required.
  • Before testosterone therapy starts, hematocrit levels have to be checked. These levels must then be checked on a regular basis to ensure the red blood cell levels are normal.


Can low testosterone levels be prevented?

Currently, there are no known ways a person can use to prevent having low levels of testosterone.

This is more so when it comes to low T caused by damage to the pituitary gland or testes or genetic conditions.

All in all, adopting a healthy lifestyle that includes regular exercise, good nutrition, weight management, and avoiding excessive alcohol and drugs can keep the testosterone levels normal.


Who should not take testosterone replacement therapy?

One of the side effects of TRT is that it can cause the prostate to grow. If a male adult has early prostate cancer, it is believed that testosterone may stimulate the growth of the cancer.

As a result, men with prostate cancer should not use testosterone therapy. It is also important for any man considering TRT to start by undergoing a prostate screening before the therapy begins.

Other men that shouldn’t use TRT include men who have:

  • Enlarged prostate that is a result of urinary symptoms
  • Men with prostate-specific antigen levels that are above 4
  • Men with a lump on the prostate which hasn’t been evaluated
  • Persons with breast cancer
  • Severe congestive heart failure
  • Persons with obstructive sleep apnea which hasn’t been treated
  • Persons with elevated levels of hematocrit


How to Boost Testosterone Levels

While testosterone replacement therapy is the most promising treatment for low testosterone levels, you can supplement it with evidence-based ways of increasing testosterone levels. Here are some of the things you can do.

  • Exercise

Exercise is the best way to avoid most lifestyle-related illnesses. It has also been found to boost testosterone levels.

A large review study concludes that people who exercise regularly have higher levels of testosterone. In the elderly, exercises not only boost testosterone levels but also increase reaction time and fitness.

New research in obese men proved that increased physical activity and a weight loss diet increases testosterone levels.

The best way to exercise and boost your levels of testosterone is to engage in resistance training like weight lifting. High-intensity interval training is very effective.

  • Eat protein, fat and carbs

What you eat affects your testosterone levels—pay attention to long-term calorie intake and diet strategy. You should, however, note that overeating or constant dieting can disrupt testosterone levels.

Eating enough proteins will help maintain healthy levels as well as help with fat loss.

Both of these are associated with fat loss. Carb intake can also help optimize testosterone levels during resistance training.

A diet based on whole foods is ideal. You need a healthy balance of carbs, proteins and fats. Doing this will optimize hormone levels as well as long-term health.

  • Take supplements

There are various supplements that claim to boost testosterone levels. There is, however, limited research to support the effectiveness of these supplements.

The best supplements for increasing testosterone levels contain any of the following: D-aspartic acid, vitamin D, Tribulus Terrestris, Fenugreek, Ginger, DHEA, Zinc, and Ashwagandha.

  • Minimize stress

Research has always highlighted the dangers of long-term stress. It can elevate levels of the hormone cortisol.

These hormones will reduce testosterone levels quickly. Stress and high levels of cortisol may increase food intake leading to weight gain and the subsequent storage of harmful body fat.

Reducing repetitive stressful situations will improve your health and hormone levels.

  • Get sufficient sunlight and take Vitamin D

Research shows that vitamin D is a natural booster of testosterone. Despite its benefits, the majority of people are deficient in vitamin D.

A recent study found that supplementing sunlight with 3,000 IU of vitamin D3 daily will increase testosterone levels by about 25%.

In the elderly, vitamin D and calcium will optimize testosterone levels, which, in turn, leads to a decreased risk of falling.



From age 25 to 30, the testosterone levels of men start to decline.

This is a major concern because low testosterone levels lead to a variety of health problems.

Healthy testosterone levels are also crucial for women. To reduce the risk of obesity, disease and premature death, you should keep your testosterone levels at normal levels.

One of the best solutions is testosterone replacement therapy. Lifestyle changes can also optimize testosterone levels. To get started, Order Blood Test to know about your levels and know if TRT is right for you.

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