|The study at hand makes protein and creatine look worse than prohormones - can that be right?|
That being said, reason #1 to take the results of the study with the necessary skepticism is a combination of false recall and flat-out lies / not disclosing one's complete "supplement" regimen. Moreover, the fact that the subjects were asked about a finite set of 30 different types of MBS powders or pills which certainly didn't include powerful designer steroids made it even easier for the study subjects to conceal some o the "supplements" (haha) they actually took. Against that background it's a bold claim to say that
"Considering the magnitude of the association and the observed dose-response trends, muscle-building supplements use may be an important and modifiable exposure that could have important scientific and clinical importance for preventing testicular germ cell cancer development if this association is confirmed by future studies" (Li. 2015).That's even more true in view of the fact that lies and recall errors are one thing that hampers the reliability of the results, while a statistically significant difference in the rate of (again) reported injuries to the groin which has long been shown to increase the risk of testicular cancer (Coldman. 1982; Oliver. 1994) is another one and reason #2 to take the results of this study with appropriate skepticism.
No, creatine does not give you cancer due to elevated DHT. As you know from a previous SuppVersity article, the increase in DHT that was observed in only one study may be statistically significant, but physiologically irrelevant (learn more).The fact that the 95% confidence levels (95% CI: 1.11–2.46 total cancer risk, 95% CI: 1.34–3.63 cancer before 25, 95% CI: 1.39–4.74 long-term use) adds another question mark to the claim that using creatine once or regularly is going to give you germ cell cancer.
|Figure 2: While both undescended testes and injuries to testes and groin can increase the risk of testicular cancer, only the latter shows a statistical significant inter-group difference between cases and controls (Li. 2015).|
"Analyses by TGCC subtype suggested similar associations between use of MBS and the risk of seminoma and nonseminoma (all the P-values for hierarchical coefficients tests were >0.05)."Against that background I would be curious how the scientists were able to do an exploratory stratified analysis which found that "both creatine and proteins increased the risk of TGCC significantly (OR =2.55, 95% CI: 1.05–6.15)" (Li. 2015).
|Table 1: Association Between MBS Use and the Risk of TGCC, Connecticut and Massachusetts, 2006–2010 (Li. 2015).|
Speaking of causality, you are aware that the "odds ratios" from the case-control study like the one at hand provide extremely weak evidence? Evidence that cannot provide any information about cause and effect? If that's not your first visit to the SuppVersity you probably knew that already. If it's not, I believe it may be worth remembering that correlation and causation are two different pairs of shoes; or, like my friend Carl Lanore likes to explain it: Just because there are firefighters all over the place, whenever a house burns down (association), they're not the cause of the fire (causation).
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