It is suggested that bioavailable testosterone represents the fraction of circulating testosterone that readily enters cells and better reflects the bioactivity of testosterone than does the simple measurement of serum total testosterone. Also, varying levels of SHBG can result in inaccurate measurements of bioavailable testosterone. Decreased SHBG levels can be seen in obesity, hypothyroidism , androgen use, and nephritic syndrome (a form of kidney disease ). Increased levels are seen in cirrhosis , hyperthyroidism , and estrogen use. In these situations, measurement of free testosterone may be more useful.
MOST MEN do not have optimal testosterone levels. If your levels are ‘normal’, you may not be in the optimal range that is best for you. “Optimal levels” mean that you feel like the best version of yourself– you have the energy to perform daily activities and workouts, you build muscle easily, and you have a healthy sex drive. No two men will experience the exact same symptoms even if they are at the same level. If your testosterone is below your optimal level, you can experience fatigue, decreased sex drive or performance, increased body fat or weight, loss of bone and muscle mass, and moodiness or irritability. Not only do these symptoms effect how you feel, but other health issues may arise such as osteoporosis or depression.