BHT was found to occur naturally in some phytoplankton. It is therefore every bit as natural as milk thistle, dandilion, and such. Though BHT as a plant extract is unavailable at this time. Synthetically produced BHT is EXACTLY the same as the plant extract. A known compound such as BHT is has EXACTLY the same molecular structure. If it did not, it would not be butylated hydroxytoluene [ BHT ]. You can read about that here: http://www.life-enhancement.com/article_template.asp?ID=2168
That was always one of the big complaints about BHT, that it was supposed to be unnatural. Another BHT myth put to rest. ...Oscar