In Brief: Can Testosterone Increase Size?
Studies have shown that testosterone supplementation alters the body composition in men with low testosterone levels. It increases lean body mass, muscle strength, bone density, and decreases fat mass. It may also influence the final adult height. However, no clear research studies are available, supporting the claim that testosterone administration increases the size and volume of the prostate.
There seems to be little evidence if the treatment with testosterone increases the size of the prostate in hypogonadal men.
The administration of testosterone for eight months to 23 middle-aged men without urinary tract symptoms increased the mean volume of the prostate by 12%.[1]
Another study involving 13 hypogonadal men showed that the volume of the prostate and seminal vesicles increased after treatment with testosterone.[2]
However, in another study, there was no significant difference in prostate volume between testosterone-treated hypogonadal men and normal men.[3]
In a randomized controlled trial involving 44 late-onset hypogonadal men, testosterone administration did not have any influence on the prostate tissue levels.[4]
Several studies showed that long term testosterone administration in men with testosterone deficiency altered body composition in men. It decreased fat mass and increased lean body mass. [5] [6]
A three-phase, randomized controlled trial involving non-obese men showed that testosterone supplementation increased lean body mass during short-term energy deficit.[7]
But they are not same as steroids.
A prospective study involving 13 non-athletic men receiving testosterone showed a small increase in fat-free mass, muscle strength, and bone density. Leaner body mass may help in controlling weight.[8]
A short term supplementation of testosterone to healthy older men with lower serum testosterone levels resulted in an increase in lean body mass and a decline in bone resorption.[9]
Open-label research involving 255 hypogonadal men showed that testosterone administration decreased body weight, waist circumference, and BMI, which were progressive over the full five years of the study.[10]
Studies also reported that testosterone supplementation affects the final adult height.
A retrospective data showed that testosterone supplementation improved first-year height velocity in boys with constitutional delay of growth and puberty compared to the boys who go through puberty without any treatment.[11]
Another study also showed that low-dose of testosterone treatment showed an initial decrease, followed by an increase in height in the boys with CDGP.[12]
The mean height velocity rose from the third-percentile to 90th percentile when adolescent boys with constitutional delay in growth were treated with low dose testosterone.[13]
Overall, testosterone supplementation influences the body composition in hypogonadal men.
There is mixed research regarding the effect of the testosterone on the prostate size.
Hence, more research studies are required to understand if the testosterone increases the size of the prostate.