The human body must get 8 essential amino acids through the diet and the other 14 are produced by the body as needed. Infants need higher levels of some….and humans with particular types of diseases may need help with some amino acids which they cannot properly process.

Someone on a strict vegetarian may need special monitoring to see if the proper mix of amino acids is provided by the diet. But a good mix of food sources usually addresses the "numbers" such that protein-deficiencies [proteins are composed of amino acid chains] are considered almost non-existent among well fed populations. You are correct to assume that any product being sold on the premise that humans need some special amino acid supplement in addition to a good diet IS A SCAM. (An exception would be someone with a particular disease such as phenylketonuria.)

It sounds like they want you to believe that the human species has somehow been limping along without their help. Some of the supplement companies try to claim that even though the human body can produce various things on its own, it is somehow "overly taxing" and you should take their supplement to make it easier. This is often the reasoning behind their selling various "enzymes" even though the body usually breaks down the enzymes which happen to be eaten and the enzymes the body needs are manufactured by the body as needed.

As always, look for INDEPENDENT verification of the science — and don’t be fooled by the various bogus "foundations" and "research institutes" that these companies create. Many even publish (and/or fund the publication) of "journals" that only exist to push their products. I have found that some of them even quote non-existent journal articles — or say things like "Harvard University researchers endorsed our product" despite denials from university officials. I’ve even seen claims made on the basis of the Physician’s Desk Reference even though PDR doesn’t even get into the subject matter often falsely attributed to it!

Of course, if a Multi-Level Marketing scheme is involved in distribution (MLM), that is another BIG RED FLAG. Also be suspicious if they emphasize that doctors hate their product because they profit from people staying sick or if they keep saying that doctors get no nutritional training in med school and are taught in a conspiracy to oppose their products — but instead they want you to trust their "certified nutritional consultants" who are specially knowledgable about these things. Some of the "product literature" I’ve been given by such people are filled with typos, misspellings, misuse of medical and biochemical terms, etc……..such that they hardly promote confidence in them!

Consider reading:
http://en.wikipedia.org/wiki/Essential_amino_acid
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