Quote:
Originally Posted by TheGuardian
I already provided a link that had studies done as well that proved a supplement like zinc does have helpful benefits.
And this from a guy that doesn't take supplements or believe in them for the most part.
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You must not have looked at the studies then....
http://www.charlespoliquin.com/Blog/...Deficient.aspx
The link you posted references 2 studies.
Here's the first:
Quote:
http://www.ncbi. .nih.gov/pubmed/21744023
Abstract
Zinc and selenium are essential minerals and have roles for more than 300 metabolic reactions in the body. The purpose of this study was to investigate how exhaustive exercise affects testosterone levels and plasma lactate in cyclists who were supplemented with oral zinc and selenium for 4 weeks. For this reason, 32 male road cyclists were selected equally to four groups: PL group, placebo; Zn group, zinc supplement (30 mg/day); Se group, selenium supplement (200 μg/day); and Zn-Se group, zinc-selenium supplement. After treatment, free, total testosterone, and lactate levels of subjects were determined before and after exhaustive exercise. Resting total, free testosterone, and lactate levels did not differ significantly between groups, and were increased by exercise (P > 0.05). Serum total testosterone levels in Zn group were higher than in Se group after exercise (P < 0.05). Serum-free testosterone levels in the Zn group were higher than the other groups (P < 0.05).There was an insignificant difference between levels of lactate in the four groups after exercise (P > 0.05). The results showed that 4-week simultaneous and separately zinc and selenium supplementation had no significant effect on resting testosterone and lactate levels of subjects who consume a zinc and selenium sufficient diet. It might be possible that the effect of zinc supplementation on free testosterone depends on exercise.
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So... for one, the study group only contained 32 people. And the results showed that simply taking Zinc and Selenium supplements had no significant effect. They attributed the differences to exercise, and not Zinc. And even so, the differences are so small that it's not really very conclusive.
It essentially says that taking the supplements by themselves had zero effect. And taking the supplements while exercising had a very small effect, but it might be simply because of the exercise.
The second study:
Quote:
http://www.ncbi..nih.gov/pubmed/21671089
Abstract
Testosterone deficiency is associated with late-onset hypogonadism. Micronutrients including copper (Cu) and zinc (Zn) influence testosterone synthesis. The association between micronutrient concentrations in hair tissue and serum testosterone was studied in Korean men. The subjects were 88 men 40-60 years of age who visited the health promotion center and an outpatient clinic of family medicine at a university hospital from March 2006 to February 2008. Population sociological features of the subjects were acquired by self-administered surveys and interview, height and weight were measured, serum total testosterone was determined in the morning, and Cu and Zn were quantified from hair tissue collected in the morning. Subjects with normal testosterone group had a significantly higher Zn level compared to low testosterone group (P = 0.003). Significant negative correlations were evident between total testosterone and Cu level (r = -0.252, P = 0.022), and the Cu/Zn ratio (r = -0.288, P = 0.008). Normal testosterone is associated with a higher Zn level. Decreased serum testosterone is significantly associated with a high level of Cu and elevated Cu/Zn ratio in hair tissue.
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This study is investigating hypogonadism in Korean men aged 40-60. Hypogonadism is a lack of hormones. Specifically in this case, testosterone. It's a little baffling as to how this study could be referenced to support Zinc intake affecting testosterone. All this study shows is that when testosterone levels are low, so are Zinc levels. It doesn't show that Zinc increases testosterone at all. It only describes the inverse relationship. When testosterone levels drop, so do Zinc levels. That's doesn't do any good in proving the opposite though.
This happens a lot. People will reference some silly study, and not bother to actually apply what the study says to the statement they're making.