Testosterone and Visceral Fat
Beer belly. Gut. Paunch. Spare tire.
Call it anything you want, but it's ugly and it's hard on your health. The
subject recently came up in The Peak Testosterone Forum. A poster asked this question:
"So I've read in several articles how visceral fat (yes, the nasty deadly one) is
harder to get rid of from diet and exercise than subcutaneous fat. I have not
seen anything that compares these two as a result of HRT. With that said, here
is a fairly obvious observation I've made from my TRT over the last 2-1/2
"...4) My waste has shrunk almost 2 belt notches after gaining this 5 to 6
pounds!...So from all of this it seems the only explanation for the belt
reduction is visceral fat removal. Does picking up your T levels significantly
cause visceral fat to fall away faster than subcutaneous? Is this fully
As you can see, this man went on HRT and is asking if the increased testosterone
could have improved his visceral (belly) fat levels? The answer is "Yes!"
Below, I will show some studies that show powerfully testosterone
can lower visceral fat. But this should be a sobering reminder to most men out there:
if a man overeats, his high testosterone levels end up creating deadly fat in
the belly area, i.e. visceral fat through signaling of preadipocytes. 
Yes, you are predisposed to deadly visceral fat!
1. Obese Men. In one study of obese men, they made no lifestyle
changes but simply gave the men testosterone therapy. The participants
experienced many positive changes, but one of them was a significant decrease in
visceral fat. As I mention in my link on Testosterone and Insulin,
testosterone has a powerful
insulin lowering effect.
What does insulin have to do with visceral fat? Well, as I discuss in my
The How and Why of Belly Fat,
regular fat tissue gets "full". Basically, your fat says, "Whoa!
That's enough, Big Fella" and then induces insulin resistance to keep more fat from being
driven into your already bloated cells. At that point the extra fat heads
for your gut and your orgams. However, testosterone literally puts the fire out,
becuase it lower insulin levels and insulin resistance. (You can, of
course, decrease insuin resistance with exercise and losing weight!) Your body
then does not panic and never forms that famed beer belly that so many jolly males
are known for.
2. Non-obese Seniors. One study put men on patches and only modestly
increased their testosterone levels by about 30% from their starting point.
Even with such relatively small changes, visceral fat decreased significantly in
these senior men. 
So it's literally no exagerration to say that if you are low or lowish T, adding
testosterone will probably melt off your visceral fat. Of course, deciding
whether or not to go on HRT is a personal decision between you and your doctor
that involves many variables, but it's always good to know the truth and the
truth is that testosterone is strongly related to your "gut".
This fact has been verified in many other ways as well. First of all, a
study on Japanese American men found that testosterone levels were inversely
associated with visceral fat.  In other words, the more testosterone,
the less the visceral fat and vice versa. Another interesting study gave a
little more understanding by essentially blocking testosterone signaling in
healthy young men.  What they found was that all fat increased, but
especially visceral fat. In other words, if you are low testosterone, you
will very much be at risk for general weight gain as well.
NOTE: See my link on How to Lower Fasting Insulin Levels
for more information of interest as well.
2) International Journal of Obesity and Related Metabolic Disorders : Journal of
the International Association for the Study of Obesity, 1992, 16(12):991-997,
"The effects of testosterone treatment on body composition and metabolism in
middle-aged obese men."
3) J Clin Endocrinol Metab, 2008, 93(1):139-146, "Testosterone therapy prevents
gain in visceral adipose tissue and loss of skeletal muscle in nonobese aging
4) International Journal of Obesity and Related Metabolic Disorders : Journal of
the International Association for the Study of Obesity, 2000, 24(4):485-491,
"Low serum testosterone level as a predictor of increased visceral fat in
5) J Clin Endocrinol Metab, 1998, 83:1886, "Testosterone deficiency in young men:
marked alterations in whole body protein kinetics, strength and adiposity"
6) American Journal of Physiology - Cell Physiology, Aug 1 2013, 305:C355-C359,
"Testosterone induces cell proliferation and cell cycle gene overexpression in
human visceral preadipocytes"