What is
Low T
Low T Defined

Low T can be caused by a signaling problem that occurs between the brain and the testicles that causes the production of testosterone to drop below normal. The brain may also signal the testicles to cut testosterone production if it feels the body has too much testosterone. Low T also can occur when your testicles can’t make normal levels of testosterone.

It is estimated that Low T could potentially affect about 1.7 million men in Canada over the age of 45.1, 2 Even though it’s natural for men to lose testosterone as they age, the medical condition hypogonadism (hi-po-na-dizm) or testosterone deficiency syndrome, also known as Low T, is not a natural part of aging. Typically, there is no cure for Low T. It is a medical condition that may require ongoing treatment.

Low T can be diagnosed by your doctor with a blood test and treated with testosterone replacement therapy (TRT).

What is Testosterone

Testosterone is a hormone made by the body. Most of the testosterone in a man’s body is produced in the testicles. In adult men, testosterone deficiencies may cause:

Brain (CNS)

  • Lack of energy, motivation, initiative, self confidence3
  • Feeling sad or blue, depressed mood3
  • Increased irritability, grumpiness4
  • Poor concentration and memory3
  • Sleep disturbance, increased sleepiness3
  • Low sex drive (libido) and activity3


  • Reduced muscle bulk and strength
  • Diminished physical or work performance
  • Increased body fat
  • Breast discomfort or enlargement
  • Loss of body hair, reduced shaving
  • Hot flushes, sweats
  • Mild anemia


  • Decreased spontaneous erections
  • Very small or shrinking testes
  • Low or zero sperm counts
  • Inability to father children


  • Height loss
  • Low trauma fracture
  • Low bone mineral density
Normal Levels of Testorone

Just like your cholesterol or blood pressure, there is a numerical range of testosterone levels (also known as T levels) that are considered normal. The brain and the testicles work together to keep testosterone in this range. When levels of testosterone are below normal, the brain signals the testicles to make more. When testosterone levels reach a normal level, the brain signals the testicles to make less. Normal levels of testosterone change as you age. Serum testosterone levels can decrease 1-2% per year after age 40.6

Signs and Symptoms

Take a look at the symptoms below to see if any apply to you.
Signs and Symptoms of Low T may include:3

  • Low sex drive
  • Increased body fat
  • Fatigue or lack of energy
  • Loss of muscle mass
  • Depressed mood
  • Decreased bone strength
  • Decreased sense of well-being
  • Sexual dysfunction (weak erections, failure to get erections)3.5

These symptoms may be a sign of Low T or other health conditions and should not be ignored. Low T can be diagnosed by your doctor with a blood test.

Take the Low T Symptoms Quiz
to find out if you may
have Low T

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The information provided in this Web site is designed to be an educational aid only.

It is not intended to replace the advice and care of your doctor, nor is it intended to be used for medical diagnosis or treatment.

Should you have any questions regarding your treatment or condition, always consult your doctor or another health care professional.

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