Testosterone and health (part one)

Last week, I took a brief look at oestrogen and how it can affect us when we inadvertently end up with too much of it swimming around.

This week, I have collected some studies on testosterone.  I’m going to see what causes it to be reduced.

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Testosterone is good for our health

First of all, let’s just remind ourselves that, unlike oestrogen, testosterone seems to be very good for our health and longevity.  Let’s take a quick look at some research conclusions:

Testosterone insufficiency in older men is associated with increased risk of death over the following 20 yr, independent of multiple risk factors and several preexisting health conditions (Low serum Testosterone and mortality in older men, Laughlin, Barrett-Connor and Bergstrom, JCEM)

In men, endogenous testosterone concentrationsare inversely related to mortality due to cardiovascular diseaseand all causes. Low testosterone may be a predictive markerfor those at high risk of cardiovascular disease (Endogenous Testosterone and mortality due to all causes, cardiovascular disease, and cancer in men, Kay-Tee Khaw, Dowsett, Folkerd, Bingham, Wareham, Luben, Welch, Day, AHA)

Low testosterone levels were associated withincreased mortality in male veterans (Low serum Testosterone and mortality in male veterans, Shores, Matsumoto, Sloan, Kivlahan, AIM)

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Things that reduce testosterone

OK, so now we’ve established that more testosterone is good for our health, let’s have a look at what reduces it.

I have to say, despite testosterone being such a great thing, it seems that there are plenty of things that can reduce our levels of it.  For such a robust, manly hormone, it does seem quite delicate…

Mobile phone radiation – it seems that mobile phone radiation reduces testosterone, in rats at least (Effects of mobile phone radiation in Wistar albino rats, Meo, Al-Drees, Husain, Khan, Imran, Saudi Medical Journal)

Fungicides – by disrupting the action of androgens during gestation, certain chemicals present in food, consumer products, and the environment can induce irreversible demasculinization and malformations of sex organs among male offspring (Synergistic disruption of external male sex hormone development by a mixture of four antiandrogens, Christiansen, Scholze, Dalgaard,Vinggaard, Axelstad, Kortenkamp, and Hass, Environmental Health Perspectives)

Some male pattern baldness treatments – it appears that male pattern baldness treatments use antiandrogens like finasteride to block hair loss.  Antiandrogens cause reductions in testosterone (ibid.)

Plastics like BPA – just as BPA seems to cause increased oestrogen levels, it causes reduced testosterone levels as well (Bisphenol A may cause testosterone reduction by adversely affecting both testis and pituitary systems similar to estradiol, Nakamura,Yanagiba, Duan, Ito, Ai, Asaeda, Tagawa, Li, Taya, Zhang, Naito, Ramdhan, Kamijima and Nakajima, Toxicology Letters)

Eating a low-fat diet – eating a low fat diet decreases your testosterone levels.  (Decrease of serum total and free testosterone during a low-fat, high-fibre diet, Hämäläinen, Adlercreutz, Puska, Pietinen, Journal of Steroid Biochemistry), and (Diet and serum sex hormones in healthy men, Hämäläinen, Adlercreutz, Puska, Pietinen, Journal of Steroid Biochemistry)

Not eating meat – it seems that not eating meat causes decreased testosterone levels (Dietary and hormonal interrelationships among vegetarian Seventh-Day Adventists and nonvegetarian men, Howie, Shultz, AJCN)

Toxic heavy metals – no, not the musical kind.  Apparently, certain heavy metals including mercury, cadmium, cobalt, and copper cause a reduction in testosterone production because of their toxicity. Other metals, including lead, zinc, aluminum, chromium, iron, nickel, and lithium, do not appear to have this effect (Toxic effect of heavy metals on cells isolated from rat adrenal and testis, Ng and Liu, In vitro cellular and developmental biology)

Diabetes and obesity – both diabetes and obesity have been strongly associated with low testosterone, so try to avoid both, if you can (Testosterone concentrations in diabetic and non-diabetic obese men, Dhindsa, Miller, McWhirter, Mager, Ghanim, Chaudhuri, Dandona, Diabetes Care)

Poor posture – by assuming a closed, subservient posture, with slumped shoulders or downward-looking gaze, you can reduce your testosterone levels.  By standing tall or sitting with an open posture and maintaining the appearance of good self-esteem, you can raise your testosterone levels (Brief non-verbal displays affect neuroendocrine levels and risk tolerance, Carney, Cuddy and Yap, Psychological Science)

Low status – it has been found that in groups of primates, the highest-ranking males have the highest testosterone concentrations while immigrant males had the lowest testosterone concentrations (Social factors increase fecal testosterone levels in wild male gray-cheeked mangabeys, Arlet, Kaasik, Molleman, Isbell, Careyand Mänd, Hormones and Behaviour)

High stress levels – it seems that stress levels are inversely related to testosterone levels in both humans and animals (Reciprocal changes in corticosterone and testosterone levels following acute and chronic handling stress in the tree lizard, Moore, Thompson and Marler, General and Comparative Endocrinology)

Lack of sleep – lack of sleep appears to reduce testosterone levels in a way that means they don’t bounce back very quickly (Endocrinological and catecholaminergic alterations during sleep deprivation and recovery in male rats, Andersen, Martins, D’Almeida, Bignotto, Tufik, Journal of Sleep Research)

Not having sex – lack of sex also means lower testosterone levels, which is ironic since often young people give up sleep so they can have sex, or in the case of most parents of young children, vice versa (Male and female salivary testosterone concentrations before and after sexual activity, Dabbs and Mohammed, Physiology and Behaviour)

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So it seems that there are quite a few things that cause our testosterone levels to go down.  And, since high testosterone levels seem to be a good thing for our health, I guess you could say that all of the things on that list are therefore bad for your health.