From the publication:

Patient interest in fertility and testicular size preservation and a desire to avoid lifelong medical therapy with testosterone drives the need to identify non-TTh [non-testosterone therapy] for hypogonadism. Medical therapies that can stimulate endogenous testosterone production include hCG [human chorionic gonadotropin], AIs [aromatase inhibitors], and SERMs [selective estrogen receptor modulators], all of which demonstrate efficacy in increasing serum testosterone levels and good safety profiles. Natural therapies to increase testosterone production include diet and exercise, weight loss, improved sleep, decreasing stress, and varicocele repair. Diet, exercise, and weight loss provide a means to potentially reverse comorbidities that are closely linked to hypogonadism. Improvements in sleep quality and duration and decreasing stress are additional lifestyle modifications that can improve testosterone levels without the need for lifelong medication. Varicocele repair also can increase testosterone levels, although rigorous data supporting its use remain lacking. Patients considering TTh should be counseled on disease modification and the possibility of discontinuing TTh in the future, before initiation of therapy, and the alternatives discussed in this review also should be considered first in appropriate candidates.

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Diet, exercise, and weight loss

– 12-wk lifestyle modification program involving aerobic exercise and diet modification significantly increased mean testosterone levels

– 52-wk program of diet and exercise significantly increased mean serum testosterone levels

– Individuals who lost 10% of weight between visits showed a significant increase in testosterone levels

– Weight loss through low-calorie diets or bariatric surgery was associated with significant increases in total testosterone levels

Improvements in sleep

– Men with OSA treated with UPPP had significant 3-mo postoperative increases in testosterone levels

– Restriction of sleep to 5 h/night decreased testosterone levels by 10-15%

Stress reduction

– Men with high stress levels had significantly lower serum testosterone levels compared with controls

– Men with higher work stress had higher than expected incidence of hypogonadism

Varicocele repair

– Varicocelectomy significantly increased mean testosterone levels

– Varicocele repair significantly increased testosterone levels

– Significantly increased total testosterone levels were found at 12-mo follow-up after varicocelectomy

– Mean serum total testosterone significantly increased after varicocelectomy