A short answer is:
DMAE Bitartrate (dimethylaminoethanol)
DMAE is a substance that is known to stabilize cell membranes.
Cell membrane degradation has been proposed as one of the prime
mechanisms of normal aging.
DMAE is a precursor to choline and acetylcholine.
It is the choline inside cells that is converted to
phosphatidylcholine, used in the building and repair
of cell membranes, especially in the brain.
And this site is mor especific to the skin. ( I love to Google)
http://www.smartskincare.com/treatments/dmae.html
Topical DMAE has recently been nominated, mostly by skin care ads and lay media, for the vacant position of the "facelift in a jar." To appreciate the scope of this claim, it is important to distinguish between topical agents that reduce the appearance of wrinkles and the ones that reduce facial sag. The former have been around for quite a while. For example, Retin A have been consistently shown to reduce the appearance of fine lines and wrinkles in some people. On the other hand, none of the well known topical agents have been proven to reverse facial sag. This is unfortunate because a sagging face is arguably a more prominent sign of aging than wrinkles. A common thinking goes that even young people may have wrinkles but only older people have sagging faces. True or not, firming is as important for facial rejuvenation as any other facet of skin care.
So what about DMAE? Can it help, or is it just another rub-on facelift scam? The reality is somewhere in between. DMAE won't accomplish anything approaching a well-performed surgical face lift, but it is not useless either. In fact, it may be the fist agent proven in a study to have at least some positive effect on facial sag.
What is DMAE and what does it do anyway? DMAE is a short for dimethylaminoethanol, a naturally occurring substance that facilitates the synthesis of a neurotransmitter acetylcholine. DMAE also may stimulate the synthesis of phosphatidylcholine, an important component of cell membranes. Interestingly, DMAE is far better known and researched as a "smart drug" than a skin firming agent. In a number of studies, DMAE has been shown to reduce age-related decline in cognitive ability and memory. It was also found to modestly increase life span of laboratory animals. An intriguing finding in some DMAE studies was that it reduced the accumulation of lipofuscin deposits inside cells. Lipofuscin is a cellular pigment consisting of aggregated chunks of molecular waste. It tends to occur in the cells of older people. It is likely that lipofuscin is not simply a byproduct of aging but also contributes to the aging process. Neurons, heart and skin of older people usually contain particularly large amounts of lipofiscin.
The DMAE-skin connection is less researched. It has been demonstrated that DMAE causes some degree of skin tightening. However, despite speculation it remains unclear how DMAE firms the skin -- whether by stabilizing the membranes, boosting acetylcholine, reducing lipofuscin deposits or none of the above. Whatever the mechanism, the effect of DMAE is often noticeable although seldom dramatic. Besides, even though DMAE can't fully reverse the existing facial sag, it may reduce its further progression. Some people report a cumulative effect with continued use of DMAE.
A number of skin care companies released DMAE creams, most costing upward of $20 for a small jar. The prices reflect the hype and relative lack of competition from "supermarket" brands. DMAE itself is a rather simple substance, no more costly than alpha hydroxy acids or aspirin.
(everything else on the page is about making your own stuff and buying their do it yourself kit.)
Hope this helps.
-D
