What Is Testosterone?

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Testosterone is the primary male hormone that plays a role in reproduction, energy, strength, and more. While it’s more prominent in males, females also have small amounts of testosterone.

Maintaining healthy testosterone levels is important for overall health and well-being. It helps to regulate libido (sex drive), bone mass, muscle mass, and the production of red blood cells.

Many factors can affect testosterone levels, including age, disease, overall health, diet, exercise, and stress. 

What Does Testosterone Do?

Testosterone plays a role in fetal development, puberty (for males), and adulthood. 

During fetal development, an embryo has either the XX or XY chromosomes. The Y chromosome initiates the growth of male internal and external reproductive organs, including the testes. 

Testosterone begins to develop in the testes in utero (during pregnancy) for those assigned male at birth. This typically starts around week seven or eight of fetal development.  

Testosterone is also an androgen. This means it is responsible for the physical changes that occur during male puberty, including:

As an adult, testosterone plays a role in libido (sex drive), bone health, energy levels, blood cell production, mood, and healthy cholesterol levels.

Those assigned female at birth produce testosterone in the ovaries and adrenal glands. It influences libido, fertility, bone health, and energy. 

How Much Testosterone Do You Have?

Testosterone levels vary from person to person and the time of day. They are typically highest in the morning. 

The the range for each sex is: 

  • Adult males: 300 to 1,000 nanograms per deciliter (ng/dL)
  • Adult females: 15 to 70 nanograms per deciliter (ng/dL)

If you suspect your testosterone is out of balance, ask your healthcare provider about a blood test to check your hormone levels.

What Happens if Your Testosterone Levels Are Low?

For males, testosterone levels increase during puberty and peak in their late 20s or early 30s. 

Testosterone gradually declines after age 30 by about 1% to 2% each year. Levels typically slow and even out when a male is in their late 40s or 50s. 

Lower testosterone levels may result from lifestyle choices or a medical condition. Anytime the hypothalamus, parts of the endocrine system, or reproductive organs aren’t functioning correctly, testosterone levels can drop.

Hypothalamus and Endocrine System

Testosterone production begins in the brain. The brain tells the endocrine system to stimulate the reproductive organs, so they produce testosterone. 

Your hypothalamus is the part of your brain that communicates with the pituitary and adrenal glands (endocrine system). It releases a gonadotropin-releasing hormone (GnRH). GnRH tells the pituitary gland to relay signals to the testes to produce or regulate testosterone levels.

Congenital (present at birth) disorders such as Klinefelter and Kallmann syndrome can result in low testosterone. They can cause babies to be born with a micropenis or undescended testes. 

Other factors that cause low testosterone in males include:

  • Testicular injury (including cancer and cancer treatment)
  • Endocrine disorders 
  • Hypothalamic disease
  • Chronic health conditions such as diabetes, cirrhosis, and kidney disease
  • Obesity (too much body fat)
  • Sleep disorders
  • Overtraining (too much exercise)

Females may experience low testosterone from:

  • Ovary removal
  • Ovarian disease
  • Endocrine disease
  • Hypothalamic disease

Signs of low testosterone in males may include:

  • Delayed puberty
  • Low sperm count
  • Increased body fat and loss of muscle mass
  • Bone loss
  • Low libido (sex drive)
  • Erectile dysfunction
  • Low energy 
  • Depression
  • Poor concentration
  • Low red blood cell production (could lead to anemia)

Some of these symptoms can be a normal part of aging. If so, they are usually mild. For example, some decrease in sex drive is normal with age, but a complete loss of interest is not typical.

Females with low testosterone can also experience decreased libido, infertility, bones that break more easily, and poor concentration.

What Happens if Your Testosterone Levels Are High?

A common reason for high testosterone levels is anabolic steroid use. This is the use of performance-enhancing drugs that athletes use to build muscle and decrease fat. Other causes of high testosterone include:

  • Adrenal tumor
  • Testicular tumor
  • Congenital adrenal hyperplasia (group of genetic disorders that affect adrenal glands)
  • Certain medications

Causes of increased testosterone unique to females include polycystic ovary syndrome (PCOS) and ovarian tumors.

Symptoms of high testosterone in male children and adolescents include:

  • Early puberty (before nine)
  • Excess pubic and facial hair
  • Early voice deepening

For adult males, naturally occurring high testosterone is rare compared to high levels from testosterone replacement therapy (TRT). A few possible side effects of testosterone treatment include:

  • Enlarged prostate
  • Cardiovascular (blood vessels, heart, and lungs) conditions
  • Worsening heart failure
  • Worsening sleep apnea
  • Mood swings, irritability 
  • Increased aggression and libido
  • Acne breakouts on the face and back
  • Polycythemia (high red blood cell count)

High testosterone female symptoms include:

  • Enlarged clitoris
  • Early puberty (before eight)
  • Irregular or missed menstrual periods
  • Acne
  • Deepening of voice
  • Excess hair growth (face, chest, inner thighs, buttocks)
  • Decrease breast size
  • Masculine features facial hair
  • Male-pattern baldness or thinning of hair

How Can You Increase Your Testosterone Levels?

Depending on your testosterone levels or symptoms, your healthcare provider may suggest artificial testosterone. It can be given by mouth, injection, pellets, skin patch, or topical (on the skin) gel. 

The following are natural approaches you can take to boost your testosterone levels. 

Increased Physical Activity

Research shows that increased physical activity helps men naturally increase their testosterone levels. This may include weightlifting, cardio, and high-intensity interval training (HIIT). But, it’s also helpful to simply get more steps per day. 

Regular exercise helps maintain a healthy weight and decrease fat, which boosts testosterone production. Exercise also increases blood circulation and reduces stress hormones.

Eat More Protein

Eating healthy amounts of protein is essential for building and maintaining muscle mass, which increases testosterone. But, it’s important to eat a balanced diet. Research shows that a very high-protein (>35%) and low-carbohydrate diet can reduce testosterone levels. Extremely low-fat diets also decrease testosterone. 

Eating foods naturally rich in zinc, magnesium, Vitamin D3, and omega-3 fatty acids supports hormonal health. The following guide tells you where you can find foods rich in these nutrients.

  • Zinc: Oysters, crab, porkchop, beans, swiss cheese, cashews, chickpeas
  • Magnesium: Pumpkin seeds, almonds, tofu, milk, oatmeal, broccoli
  • Omega-3 fatty acids: Salmon and other cold-water fish, walnuts, flaxseed oil, and chia seeds
  • Vitamin D3: Eggs, mushrooms, and fortified dairy products (sunshine exposure also increases vitamin D)

In short, eating a healthy diet involves:

  • A balanced diet (eating a variety of food groups in moderation)
  • Avoiding processed foods
  • Including fresh fruits and green, leafy vegetables
  • Eating lean meats 
  • Eating healthy fats 

Reduce Stress Levels

Stress raises cortisol (stress hormone) levels in the body. Chronic stress causes the body to produce high levels of cortisol over extended periods of time. This can cause weight gain, certain health conditions, and lowering of testosterone production. 

While not everyone enjoys the same activities, here are a few ideas to help you reduce stress:

Many people wonder if masturbation affects testosterone levels. While it may have a short-term effect for a few minutes, studies have yet to show a significant difference. However, the most current research suggests that more research is needed to be sure.

A Quick Review

Testosterone is primarily a male hormone that plays an important role in reproduction, libido, energy levels, bone mass, puberty, and more. While it is primarily a male hormone, females also have small amounts.

Testosterone levels vary throughout the day, and are typically higher in the morning. They also vary with age and sex assigned at birth. 

Adult males testosterone levels range from 300 to 1,000 nanograms per deciliter (ng/dL). Adult females levels are in the 15 to 70 nanograms per deciliter (ng/dL) range. 

Exercising, eating a well-balanced diet, and decreasing stress levels are all great ways to increase your natural production of this vital hormone. 

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