There are many things in everyday life that can easily lower testosterone
and many of them go against societal norms and conventional thinking.
This is important because it only takes one weak link to drop the bottom
out of your testosterone levels. It
only takes one mistake or one area of ignorance to significantly decrease this
all-important hormone. Thus, the intelligent testosterone lover will take a few
minutes and look through the following list and do a quick self-examination.
Research has shown that every one of these items can lead to very signficantly
lowered testosterone (and libido). I call them the Dirty Dozen.
NOTE: You may also want to read my link on
Common Chemicals That Lower
Testosterone as well.
Need to boost your Nitric Oxide naturally through food, drink and supplements? Check out Lee Myer's book here:
The Peak Erectile Strength Diet
Or do you need the most comprehensive testosterone book in Amazon? Here it is:
Natural Versus Testosterone Therapy
1) Overweight. Those extra pounds are strongly correlated with lower
testosterone  and a Lot of Other Bad Stuff as well.
Metabolic Syndrome (insulin resistance) and diabetes are both equate to
decreased testosterone levels. 
3) Chronic and Non-Moderate Alcohol Consumption. Animal studies clearly
show heavy drinking for an extended period of time will lead to
lower testosterone. 
Always play it safe with Alcohol and limit yourself to one or two drinks per
4) Stress. We males can intuitively feel how hard stress is on our body and
mind and the reason is, among other things, simple chemistry: stress increases cortisol and cortisol has been shown repeatedly
to be associated with lowered testosterone levels. I cover this
extensively in my link on
Stress, Testosterone and Your Brain.
5) Lack of Sleep. This actually follows - and many guys don't know this -
as really a subcategory of #4. Lowering sleep quantiy or quality will
leads to increased cortisol and a corresponding testosterone decrease and I
cover that extensive in my link on the
Nasty Effects of Lack of Sleep. Sleep can also lead to
calcification, or hardening, of the arteries and blood sugar management issues
6) Depression. Depression is also actually a subcategory of #4 and leads to
increased cortisol and inevitably lowered testosterone levels. Depression
also can lead to erectile dysfunction and literal brain damage as well. Read my
link on Depression for more details.
7) Vitamin A Deficiency. Being deficient in Vitamin A has nasty results on
both sperm and testosterone. In fact, animal studies show that in Vitamin
A-deficient animals, lower testosterone is followed by atrophy of the testes.
 Don't forget that you don't have to directly consume Vitamin A to get
your what your body needs: your body can also build it from betacarotene,
the orange phytochemical in yams and carrots.
8) Vitamin D. Vitamin D has been correlated with higher total and free
testosterone.  Vitamin D deficiency is incredibly common, as I cover in
this link on Vitamin D, and can result from being indoors, skin color, the
seasons and so on. The solution, of course, is to take Vitamin D as a
supplement in order to avoid lower testosterone. (Read my link on Vitamin
D for more information.)
9) Overtraining. If a little exercise is good, then a lot has to be better,
right? Unfortunately, that doesn't apply when it comes to our hormones.
Overtraining lowers many of our most precious hormones, such as testosterone,
and raises still others that ought not to be raised. You must build up
slowly in your training endurance and strength and make sure you have sufficient
rest. Read more in my link about Overtraining's
Powerful Testosterone Lowering Abilities.
10) Toxins. There's a lot of what I call
"Socially Acceptable Chemicals" that will give you lower
testosterone. In fact, it's nearly impossible for a modern urban dweller
to escape at least some exposure to these nasty hormone killers, which include
and Marijuana. Read these links:
no one but you can protect your testosterone.
11) Varicocele. These are nasty distended and/or tangled systems of veins
near the testicle that can affect testosterone and fertility. I had one young
reader write in who knew exactly when this occurred: during a squat at the
(See my link on
Fertility for details.)
12) NEWS FLASH: This is hot off the press: rapidly increasing blood sugar
levels lead to significantly decreased testosterone.  In fact, blood sugar elevation can whack
testosterone by as much as 25%! Over 95% of the men in the above study, both with normal
glucose clearance and diabetic, had their testosterone significantly lowered for
hours by a glucose drink. Again, you must manage the Glycemic Load
of your foods. Read this link on
How Sugar Lowers Your Testosterone and Assaults
Your Sex Life.
NEWS FLASH #2: The Atkins (or Low Carb Diet) received yet another
black eye from scholars at the University of North Carolina.
Researchers there found that a low carb (30%) diet lowered testosterone by about
a third and increased cortisol by about a seventh (15%) when compared to a high
carb (60%) diet after some intense training.  The testosterone to cortisol ratio is incredibly important
to male long term health and this hammered it from both ends.
14) Fenugreek. Watch out for this herb (at least the seeds) that hail from
India, China and other parts of Asia. Several animal studies show a
decrease in both testosterone and fertility. 
Mercury will also lower your androgens, but unless you are eating a lot of fish, this
shouldn't be an issue for you. Also, I
highly encourage you to read about my link regarding
unlike Mercury, this is so prevalent in our foods and supermarkets thanks to the
FDA and Food Industry and will take out both your Brain AND your hormones.
NOTE: You should also read my section on
Free Testosterone as there I
discuss several things that can uniquely lead to lower
Free Testosterone as well.
Free Testosterone is the
bio-available serum testosterone that can actually "do work" in your tissues.
Remember that this is not a cumulative list. However, it only takes ONE of these to
severely reduce your T-levels 30%
or more. Remember that low testosterone is associated
with heart disease, diabetes, Metabolic Disorder, depression and
osteoporosis in males.
NOTE: Please read this link on How
Marijuana Can Destroy Your Hormones, Fertility and Lead to Impotence.
1) Intl J of Impotence Res, 2009, 21:89–98, "Obesity, low testosterone levels
and erectile dysfunction"
2) Francis Hayes, The results were presented at The Endocrine
Society’s 91st Annual Meeting in Washington, D.C. This was not published
even online at the time of writing but was covered extensively in the health and
3) Natl Inst on Alcohol Abuse and Alcoholism, "Alcohol and the Male Reproductive
System", Mary Ann Emanuele, M.D., and Nicholas Emanuele, M.D.
Reproduction, 2002, 124:173-180,
"Regulation and Perturbation of Testicular Functions by Vitamin A" (Review)
5) Clin Endocrinol (Oxf), 2009 Dec 29, [Epub ahead of print], "Association of
vitamin D status with serum androgen levels in men"
6) European journal of applied physiology, 2010 Apr, 108:1125-1131, "Influence
of dietary carbohydrate intake on the free testosterone: cortisol ratio
responses to short-term intensive exercise training."
7) Contraception, 73(3):301-306, "Evaluation of the potential antifertility
effect of fenugreek seeds in male and female rabbits"
8) Phytotherapy Research, Mar/Apr 1993, 7(2):134-138, "Efficacy of the steroidal
fraction of fenugreek seed extract on fertility of male albino rats"