"The body doesn't care where it gets its chemicals from"
Sometimes it does, or maybe the supplements are not formulated quite right. E.g. I saw this at LessWrong: "turns out that fish oil pills suck, and you’d need to take approximately 9 times as much to have the same effect as eating fish, at which point they’d have dangerous blood thinning effects."
Link to the study: http://www.ncbi.nlm.nih.gov/pubmed/12848287
Even more concerning with supplements is what has been seen in New York. A significant percentage of herbal supplements sold contained large quantities of bulking material and in some cases that was all they contained.
Which means everyone out there taking supplements would likely be less healthy than people eating food in a balanced manner.
Sometimes it does, or maybe the supplements are not formulated quite right. E.g. I saw this at LessWrong: "turns out that fish oil pills suck, and you’d need to take approximately 9 times as much to have the same effect as eating fish, at which point they’d have dangerous blood thinning effects." Link to the study: http://www.ncbi.nlm.nih.gov/pubmed/12848287