TReaTing Diabesity With Testosterone!? If You Keep DHT in Check + Stay Away From Aromatase Inhibitors, It May Work

It probably won't turn an overweight pre-diabetic into a fitness model, but a getting a TRT script has the potential of changing a man's physical and psychological health for the better.

Despite the fact that more and more men recognize the benefits of supervised testosterone replacement therapy (TRT) and the bodybuilding and fitness community cherishes 'their BIG T' as the be-all-and-end-all, many medical practitioners look at the administration of exogenous androgens as a potential health hazard. I would even bet that it won't be difficult to find one or two MDs who would say that Patricia S. Juang et al.'s idea to administer testosterone to obese men with normal, but low baseline testosterone levels to improve their body composition and insulin sensitivity borders physical injury - and that irrespective of adjuvant 5α-reductase (dutasteride) or aromatase (anastrazole) inhibitor administration.

TRT w/ or w/out aromatase or 5α-reductase inhibitor?

It goes without saying that the bodybuilding enthusiasts will think very differently about the usefulness of the 10 g testosterone gel (Testim) the fifty-seven 24–51-year old men with free testosterone levels in the lower 25% of normal range (<0.33 nmol/L) and a body mass index of ≥30.0 kg/m² in this recent  98-day randomized, double-blind, parallel group, placebo-controlled trial from the Universities of California and the Boston University Medical Center (Juang. 2013). In fact, I am pretty sure that, contrary to the scientists who put their subjects on either

• + subjects received a gonadotropin releasing-hormone antagonist to suppress endogenous T production
  10g Testim per day,
• 10g Testim + 1mg Arimidex (anastrazole) per day, or
• 10g Testim + 2.5 mg Avodart (dustasteride),

some of the physical culturists may even have suggested to use both, the aromatase inhibitor Arimidex and the 5α-reductase inhibitor Avodart to make absolutely sure that the T remains T and is not converted to estrogen or DHT.

Figure 1: Change in hormone levels (left) and body composition (right) after 98 days on 10g t-gel (Testim) with / without aromatase (Arimidex) or 5α-reductase (Avodart) inhibitor (Juang. 2013)

If they looked at the data in Figure 1, the estrogen-phobic bodybuilding enthusiasts would yet have to admit that the "bad estrogen" cannot be so bad as broscience would have it. Only minimal decreases in body fat, and significantly lower increases in fat free mass in the presence of a 5cm! (+4%) increase in waist circumference is certainly not what the bros are looking for.
As surprising as the magnitude of the 'waist gain' may be, I personally have been more surprised by the effects the 10g of Testim had on the DHT levels of the overweight subjects. In both, the T-only and the T + Arimidex group the DHT level literally exploded and blunted the 25%, respectively 30% increase in glucose disposal during  minutes 120–180 and 240–300 of the euglycemic hyperinsulinemic glucose clamp test the scientists performed before and after the intervention period (Juang. 2013).

Despite a -40% decrease in PSA (vs. +9% in the T-only group), the 5α-reductase inhibitor dustasteride did not prevent the ~10% increase in prostate size that occurred in both the T-only (12%; +9% PSA) and T + Acodart (10%; -40% PSA) group. Other safety markers, such as AST (liver) or haemoglbin (iron overload) did not change.
References:

• Juang, P. S., Peng, S., Allehmazedeh, K., Shah, A., Coviello, A. D. and Herbst, K. L. (2013), Testosterone with Dutasteride, but Not Anastrazole, Improves Insulin Sensitivity in Young Obese Men: A Randomized Controlled Trial. Journal of Sexual Medicine.