• Testosterone replacement therapy can have dramatic effects on your appearance, especially if you do it in conjunction with an exercise program and a healthy diet.
• Body Fat — Body fat levels begin to decrease in 1 or 2 months, but this loss may take 2 to 3 years to plateau.
• Waist Size — Just as with body fat in general, you should expect your waist size to start to decrease in 1 or 2 months. Expect to lose approximately 3.5 inches in the first year after starting therapy.
• Muscularity — The amount of muscle you gain is dependent on genetics, exercise, age, and diet, but you should start to see more muscle in as little as a month.
2. Sexual Benefits
• Testosterone replacement therapy does a lot more than just increase your sex drive. TRT patients generally report stronger and more frequent erections and ejaculations, in addition to a more satisfying sex life in general.
• Sexual Desire, Thoughts, and Fantasies — You could feel an increase in libido in as little as a week, but generally, it takes about three weeks for things to really start to percolate, generally plateauing at about the 9th week.
3. Psychological Effects
• A lot of people don’t realize it, but psychological problems like depression and anxiety might have their roots in low testosterone levels. Also, positive psychological traits like sociability and “appropriate aggressiveness” might be associated with higher testosterone levels. (“Appropriate aggressiveness” refers to asserting yourself or acting confidently, such as mustering up the courage to ask the boss for a raise or asking a woman out to dinner.)
• Anxiety Levels, Appropriate Aggressiveness, Sociability, Mental Wakefulness, and Creativity should start to improve
• Depression –– Depression, or even increased levels of sadness, should start to decrease by about week 6, but maximum effects take longer and vary widely from individual to individual.
4. Health Benefits
• Insulin Sensitivity — Without good insulin sensitivity, a good portion of the food you eat gets transported to fat storage instead of being used to build muscle. The more insulin sensitive you are, the better, and TRT starts to increase insulin sensitivity in just a few days, but often continues for several years.
• Bone Density — While osteoporosis is more often a problem with aging women, men with low testosterone levels can also have signs of diminishing bone density. However, restoring testosterone levels to normal or high normal can show positive effects on bone density in about 6 months and continue for at least 3 years.
• Inflammation — Inflammation plays a big role in just about every human disease, especially heart disease, and TRT generally starts to calm inflammation in 3 to 12 weeks.
• Blood Chemistry — Total cholesterol and LDL (but not HDL, i.e., “good” cholesterol) generally start to decrease by about week 4 and continue to improve for 6 to 12 months.