Although sometimes referred to as ‘the male hormone’, testosterone is present in varying levels in both men and women. Testosterone impacts a variety of different physical and behavioural attributes, including increasing energy levels, controlling the sex drive and influencing competitiveness.
In men, testosterone is important for:
- Development during puberty
- The creation of sperm
- Strengthening bones and muscles
In women, testosterone is key to:
- The maintenance of healthy levels of other hormones
- The creation of new blood cells
- Fertility and sex drive
Normal Testosterone Levels in Men
Testosterone is measured in nanograms per decilitre of blood (ng/dl) and the following list illustrates healthy levels for different age groups.
- 0-5 months – 75-400 ng/dl
- 6 months-9 years – less than 7-20 ng/dl
- 10-11 years – less than 7-130 ng/dl
- 12-13 years – less than 7-800 ng/dl
- 15-16 years – 100-1,200 ng/dl
- 17-18 years- 300-1,200 ng/dl
- 19 years and over – 240-950 ng/dl
Normal levels of testosterone in men range from 240 to 950 ng/dl, with male testosterone levels peaking in the late teens or early 20’s. After the age of 30, the average man can expect to see their levels decline by 1% every year.
Measuring testosterone can be complex, however, as levels naturally fluctuate throughout the day. Men aged 40 and under will typically experience greater fluctuations than men in their 70s. For some context here, an average 40-year-old might have a testosterone reading at 8 a.m. that is 200 points higher than their reading at 8 p.m., whereas a 70-year-old might only see a difference of 50 points between these times.
Additionally, there are a variety of external factors that can impact testosterone readings. High-intensity workouts are known to increase testosterone and a 1998 study measuring testosterone levels among basketball fans found that supporters of winning teams saw their levels increase, whereas supporters of the losing teams experienced a marked decline in their testosterone levels. Gains and losses from these types of activity typically subside within an hour or so, however, there are factors such as obesity that will have a more lasting effect.
Signs of Low Levels of Testosterone in Men
Low testosterone is a widespread issue amongst men and recent studies have indicated that approximately 5% of men aged between 50 and 59 display some of the more common symptoms.
Most men with low testosterone will initially start to notice a general decline in their:
- Physical energy
- Concentration and motivation
Additional indicators of low testosterone in men can include:
- Weight gain
- Reduced libido
- Erectile dysfunction
- Aching joints
The number of men seeking treatment for low testosterone is significantly lower than the number of men thought to be affected. This can have health implications as low testosterone is a risk factor for a variety of health conditions including heart disease and diabetes.
An Overview of Typical Testosterone Levels in Women
- 0-5 months – 20-80 ng/dl
- 6 months-9 years – less than 7-20 ng/dl
- 10-11 years – less than 7-44 ng/dl
- 12-16 years – less than 7-75 ng/dl
- 17-18 years – 20-75 ng/dl
- 19 years and over – 8-60 ng/dl
Normal levels of testosterone in women aged 19 and over typically range between 8 and 60 ng/dl. Testosterone is primarily produced in the ovaries of premenopausal women and after menopause levels often decline rapidly. This usually occurs between the ages of 45 and 55.
Symptoms of Excess or Low Testosterone in Women
Oestrogen levels drop in women after the menopause, which can increase levels of male hormones. There are also certain diseases such as polycystic ovarian syndrome (PCOS) that can increase testosterone levels.
Symptoms of excess testosterone in women can include:
- Loss of hair on the scalp
- Increased facial hair
Similarly to men, low testosterone levels in women can cause a loss of libido, osteoporosis and fertility issues.
If you think you might have low testosterone levels, contact your doctor to discuss your options. Reduced testosterone levels are often just a normal part of the ageing process, however, it might also be a sign of an underlying condition.