Confusing Study Results: Saliva Testing "Adequate" For Free Testosterone, Yet Way Off For Cortisol!?

Many of us spend a fortune on "hormone optimization", but when it comes to actually testing our levels, most of us are pretty cheap: "200$ for labs? No way I rather buy another test booster for that money - won't hurt, I guess!" And even, if we finally decide to test our testosterone levels, we will usually choose the cheapest and most convenient testing method: saliva testing. But is this an adequate way of assessing one's hormonal status? Although these tests have been around forever, nobody appears to be sure how reliable they actually are. A recent study (Caenegem. 2011) from the University Hospital of Ghent, Belgium, attempts to provide answers.

The researchers tested two saliva collection methods, chewing on a cotton swab (Salivette, Sarstedt) and passive drooling on 30 healthy males with a median age of 27 years (range 19–65 years) and compared their findings against serum levels, which were measured on the same occasion. Here are their results:

For cortisol, we observed a mean positive bias of 65% for passive drooling versus Salivette. In addition, cortisol determined on passive drooling samples correlated much worse with calculated free cortisol than cortisol analyzed on the cotton samples (respectively r=0.34 versus r=0.70). However, for testosterone passive drooling correlated well with the calculated free fraction (r=0.66). A positive bias of 21% for testosterone collected by passive drooling versus Salivette was observed. In contrast to earlier reports, we found no artefactually high testosterone results with the cotton-based collection method.

Obviously, these results seem to indicate that saliva testing for testosterone is a good, while saliva testing for cortisol is a bad idea, BUT these results are in fact intrinsically flawed. By just calculating free serum values instead of using equilibrium dialysis to actually measure them, the scientists' control values and with them their assessment of the "appropriateness" and "inappropriateness" of salivary testosterone, respectively cortisol testing are questionable. 

From what I hear from practitioners like Dr Crisler, it is highly advisable to spend the extra cash to have measured (not calculated) serum testosterone levels as reliable baseline and 4x saliva cortisol profiles to see where your levels are at throughout a 24h period. Arguably, this is yet another case in which a questionable study design leads to results which refute common practice and aggravate a confusion around hormonal testing procedures which affects practitioners and patients, alike.

Positive/Negative Effects of Normal/High DHT on Metabolic Pathways

Regular visitors of the SuppVersity will certainly remember some of my previous posts about the false demonization of DHT. A new study coming from the Institute of Endocrinology in Prague (Duskova. 2010) supports the view that "optimal" and not low DHT levels are what men should be striving for.

Theorizing that DHT as a non-aromatizable androgen could be responsible for a male type fat distribution, the scientists reviewed the results of both animal and human studies and found that "physiological levels of DHT [do not only] inhibit growth of mature adipocytes", but also have positive levels on body composition in patients on hormone replacement therapy (HRT). On the other hand, there is also evidence that high (super-physiological) DHT levels are associated with obesity:

In obese people, DHT metabolism in adipose tissue is altered. Local abundance of non-aromatizable androgen has a negative effect on adipose tissue and it could be involved in pathogenesis of metabolic and cardiovascular diseases.

So, in view of getting/staying lean and healthy, you want your DHT levels within normal ranges and you certainly don't want to block it by taking Saw Palmetto or (God forbid) Finasteride or other drugs out of fear of developing prostate cancer, even if you do not even know if your DHT levels are pathologically elevated.