There are multiple ways for a man in his 30s to have low testosterone.
All men in the West are experiencing plummeting testosterone levels due to:
1. Chronic stress levels - cortisol increases effecting test. production.
2. Diet - certain foods increase test. levels and many decrease test. levels. Examples of foods that decrease test. levels are foods that are sprayed heavily with pesticides; soy (this is a double whammy since they are heavily sprayed and contain xenoestrogen). Foods that increase test levels are cruciferous vegetables (broccoli, Brussels sprouts, cauliflower).
3. Plastic containers - again they contain xenoestrogen.
4. Lavender - reduces test. levels; found in just about every cologne/perfume out there.
5. Tea tree oil - reduces test. levels can cause gynecomastia in boys. Found in shampoos and shower gels.
6. Lack of sleep - reduces cortisol, increases growth hormone and test. levels.
7. Cancer - one of the early warning signs of testicular cancer is falling test. levels.
8. Depression - This will absolutely KILL test. levels.
9. Damage to the testes.
10. Lack of good fat - test. is made from cholesterol.
11. Cancer in general.
12. Too low calorie intake.
13. Too high calorie intake.
14. Traumatic brain injury.
I could go on but those are just a few.