There are several factors that can decrease testosterone levels in men. Here are some of the most common ones:

• Excess weight: Obesity can lower testosterone levels and increase estrogen levels, which can lead to a number of negative side effects.

• Sedentary lifestyle: Lack of physical activity can also lower testosterone levels.

• Hair-loss treatments: Some hair-loss treatments, such as finasteride, can lower testosterone levels.

• Smoking and excessive alcohol use: These are controllable factors that can diminish testosterone levels.

• Certain foods: Some foods, such as soy, nuts, fish, spearmint tea, red reishi mushrooms, flaxseed, and refined carbohydrates, have been shown to have detrimental effects on testosterone levels.

• Certain medications: Certain medications, such as SSRIs (a type of antidepressant), can interfere with the brain chemicals necessary to make testosterone.

• Substance and drug abuse: Substance and drug abuse, such as alcohol, opioids, and anabolic-androgenic steroids, can affect testosterone production and interfere with testicular and hypothalamic-pituitary function.

• Age: While testosterone levels may naturally decrease as men get older, there are many other factors that can contribute to low testosterone levels.

Its important to note that low testosterone levels can have a number of negative side effects, including decreased muscle mass, increased breast tissue, loss of strength, sudden weight loss, irritability, and mood swings. If you are experiencing any of these symptoms, its important to talk to your doctor about getting your testosterone levels checked.