Testosteron is a hormone produced by the body. In men, testosterone is mostly produced in the testes and is responsible for stimulating sperm production, sex drive, build muscle and bone mass.

With increasing age men, testosterone production decreases gradually. If the decline is more than they should, men can experience a variety of different specific symptoms and complications.

Here are 9 signs of decline in testosterone production in men as reported healthline,  among others:

1. Low Sex Passion

Testosterone play a role in regulating a man’s libido. With age, most men will experience a more drastic reduction of sex drive. Low levels of testosterone can also make it difficult to reach orgasm.

2. Erection Difficulties

The hormone testosterone also helps men achieve erections. Testosterone itself does not cause an erection, but it stimulates receptors in the brain to produce nitric oxide, a molecule that triggers an erection.

Low testosterone is associated with many conditions that cause erectile dysfunction, including obesity and diabetes atherosclerosis.

3. Low Semen Fluid Production

Testosterone also play a role in the production of semen, the fluid that helps sperm development. Men with low testosterone will see a reduction in the amount of sperm when ejaculation volume.

4. Hair Loss

Hair production is also influenced by the hormone testosterone. Baldness is a natural thing when men get older, but men with low testosterone may experience more rapid hair loss before old age.

5. Tired Easily

Men with low testosterone tend to be gluttonous and less energy in their daily activities.

6. Loss of Muscle Mass

Because testosterone also has a role in the development and strengthening of muscles, men with low testosterone may have decreased muscle mass and strength, especially in the hands, legs, or chest.

7. Obesity

Men with low testosterone will increase body fat. Although the reason behind this is less clear, studies have shown that the genes that control body fat percentage is also responsible for circulating levels of testosterone in men.

8. Decrease in Bone Mass

Weakening of the bones or osteoporosis is often called is considered as a condition that occurs only in women only.

Men with low testosterone also may experience bone loss due to the production of testosterone can help strengthen bones. As a result men are more prone to fractures, usually in the hips, legs, ribs, and wrist.

9. Unstable mood

Women often experience mood swings during menopause, when estrogen levels drop them. Men with low testosterone levels can also experience the same symptoms.

Testosterone is often described as “fuel” to the man who can improve mood and mental capacity. Research has shown that men with low testosterone were more likely to experience depression, irritability, or difficulty focusing the mind.