Q: What is Chiral or Chirally Correct
when referring to ingredients or molecules?
A: A molecule is considered chiral (ki- rhul) if it differs
from its mirror image. The easiest way to visualize this is to do the following: Hold out
your hands (palms up or down). You will see that they are mirror images of each other. Next, place your right
hand on top of your left hand. You will see their major features do not line up, and, no matter
how you try, they can’t line up (non-superimposable). Your left and right hands are made
of the same anatomical structures (fingers, joints, etc), however, in a mirrored configuration. This means your hands
are chiral. We call a molecule
achiral if it does not differ from its
mirror image (superimposable). An example of something achiral are the letters “A”
“O” or “T” (as shown below). Its
original version does not differ from its mirrored version, and when placed on top of each other their major features line
A A O
O T T
Where does the term "chiral" come from?
A: The word chiral
actually stems from the Greek word "kheir", which means “hand”. Just like we have a right and
left hand, a chemical’s molecule can exist in right and left hand forms.
Q: How do I know if an ingredient (molecule) is chirally-correct?
To identify which molecular hand is being represented the prefixes "D" and "L" are used: “D”
, (Dextrorotory)- means the polarized light rotates to the right (clockwise) and “L”, (Levorotary) means
light rotates from left. For example: D-alpha-tocopherol and L-alpha-tocopherol. Both are vitamin E,
but just in mirrored orientations. So, if the forms are technically the same chemical, why is it so important to distinguish
between them? Because the different forms can actually result in different chemical reactions.The term “Chirally-Correct”
is given to whichever hand is specifically isolated due to its superior benefits and compatibility with nature (including
the human body).
Q: Where do Chirally-correct ingredients come from?
A: Some chiral compounds are
extracted from nature and are already Chirally-Correct. But, since we want these natural ingredients (molecules) faster
than the Earth creates them, many compounds are artificially created in a laboratory. Unfortunately, when these molecules
are generated in a lab, they generally are compounded as in aracemic form, which means the left and the right hands are
joined. We often refer to this as a 50/50 combination. The racemic form is identified with the prefix “DL”,
which represents both the left- and right-handed molecules being bonded together. Racemic molecules are not Chirally-Correct,
and either react in a way that is not beneficial (irritation, inflammation, allergic or toxic reactions) or in a way
that actually negates the primary function of a specific ingredient. DL-alpha-tocopherol has been shown to have a higher
incidence of causing allergic reactions in people, thus it is more common to use D-alpha-tocopherol as an ingredient in personal
and nutritional products.
Q: How do
we get a “chirally-correct” molecule?
A: We get a chirally-correct
molecule through a meticulous separation process called isolation, (we call it Purification). Racemic molecules
are split into the two separate hands so that the Chirally-Correct forms can be isolated and extracted. DL-alpha-tocopherol
becomes D-alpha-tocopherol and L-alpha-tocopherol. But, since L-alpha-tocopherol has shown to be virtually functionless,
only the D hand is utilized. Terribly, had pharmaceutical manufacturers put Thalidomide through chiral separation years
ago, many women would not have had children with debilitating birth defects – it was only the racemic form of the drug
that was toxic, whereas the Chirally-Correct form (available on the market today) is both safe and effective.
Another note to take into considerations is that your body only recognizes amino acids in the
“L” form. If you look at amino acid products in a health food store, you will notice that allof the amino acids have “L” before their name.
This is again, the "chirally-correct" form of an amino acid that your body can properly communicate with.