One study on humans - with autistic children - showed that the oral liposomal group (compared to the transdermal group) exhibited some increases in plasma reduced glutathione, but not in whole-blood glutathione levels following supplementation. The authors stated: "We did not see a change in whole-blood glutathione which suggests that increasing intracellular glutathione may require the use of precursors or building blocks for glutathione". Both groups also showed increases in plasma sulfate and cysteine which the authors attributed to actual breakdown of glutathione in the body.( A clinical trial of glutathione supplementation in autism spectrum disorders. Kern JK et al. Med Sci Monit. 2011 Dec;17(12):CR677-82). This human study was not blinded or placebo-controlled which is the golden standard in medical research.
In Ancient Rome , fellatio was considered profoundly taboo.  Sexual acts were generally seen through the prism of submission and control. This is apparent in the two Latin words for the act: irrumare (to penetrate orally), and fellare (to be penetrated orally). Under this system, it was considered to be abhorrent for a male to perform fellatio, since that would mean that he was penetrated (controlled), whereas receiving fellatio from a woman or another man of lower social status (such as a slave or debtor) was not humiliating. The Romans regarded oral sex as being far more shameful than, for example, anal sex – known practitioners were supposed to have foul breath and were often unwelcome as guests at a dinner table.