When you see a mineral ingredient that has "glycinate" appended to the
name of the mineral, this means that the mineral has been chelated
with an amino acid called glycine. I'll define some of these terms,
and discuss the possible benefits of choosing a glycinated mineral.
First, a brief look at glycine itself. Glycine is a "nonessential"
amino acid. This means that the body can manufacture it, and that
outside dietary sources are not required for proper nutrition.
Glycine, which is produced in the liver, is the smallest and simplest
of the amino acids, and is a "building block" for other amino acids.
Amino acids are structural elements of the body's protein molecules.
More on glycine:
AnyVitamins: Glycine amino acid information page
Molecular Expressions: Glycine
Springboard4Health: Glycine - Amino Acids
Chelation, in relation to this subject, is the pharmaceutical process
of bonding a mineral to an amino acid. When this is done, the
absorption and "bioavailability" of the mineral may be increased,
meaning that the delivery of the mineral and its usability by the body
can be enhanced:
"There are three kingdoms in the world--animal, vegetable or mineral.
And while many animals, including man, can produce most essential
nutrients within their bodies, minerals must be ingested. However,
it's not just what you eat, it's what you absorb. Because of this,
mineral suppliers are exploring ways to maximize absorption and
Bioavailability can be defined as the amount of a nutrient ingested
that is absorbed and available for cellular metabolism. One of the
natural means of increasing bioavailability of minerals is chelation.
The process involves bonding minerals, such as zinc or iron, to amino
acids, in a stable form. Because the body is highly efficient at
absorbing amino acids through the intestinal wall during digestion,
chelation delivers the minerals at the same time."
Health Supplement Retailer Magazine: Chelazome
"Amino acid chelates - a stable chemical complex between the mineral
and more than one site on an amino acid, the building blocks of
proteinare another form of mineral preparations. Various processes
that produce different degrees of chelate stability- and possibly
differences in absorption properties - mean that results for one
chelated product may not equal identical results for another... Many
studies on mineral chelate bioavailability have been conducted by
their producers and have not been published in peer-reviewed
publications. Nonetheless, independent researchers have published a
few journal articles detailing results that show better absorption for
certain amino acid chelates than for their inorganic counterparts. In
one such study, researchers compared bread fortified with an iron
chelate (bis-glycinate) to iron sulfate-enriched bread. They reported
double the apparent absorption from the chelate than from the
Nutrition Science News: Mining Mineral Supplements
"How does a chelated ingredient work? The body believes an amino acid
chelate is a small protein molecule, and so treats it as such. The
mineral is therefore protected from going through a chemical reaction
in the stomach and reaches the small intestine intact, where it is
then absorbed by the body through active transport. Once in the
tissue, some metabolism will take place and the mineral will be
removed from the chelating agent and bond to other transport molecules
to move throughout the body."
Natural Products Insider: Delivery Systems
"Why use mineral chelates or mineral yeast chelates?
Amino acids can form mineral chelates that have good bioavailability.
In order for a mineral to be bioavailable, there are two main
requirements: The first is that the mineral must be readily absorbed
into the body so that it can be used. The second requirement is that
the mineral be in a form that is useable by the body.
In order for a mineral to be bioavailable, it must be soluble to some
degree in the intestine where absorption of the mineral takes place
(large particles cannot penetrate the wall of the intestine). Thus
some mineral forms depend on acid in the stomach to convert the
mineral to a soluble form before absorption can take place, and other
forms of minerals are not well absorbed because they are not soluble
in the intestines. Some soluble inorganic may react in the digestive
tract to form less bioavailable mineral forms. Amino Acid chelates are
resistant to this type of chemical reaction. They are also generally
soluble to some degree, and are readily absorbed into the body so that
the mineral can be used... The purpose of chelated minerals is to
surround a metal ion with an organic molecule that can be better
absorbed in the human body. "
Kelatron: Questions and Answers
There may be some benefit to choosing a multi-vitamin/mineral
supplement which includes chelated minerals (such as the ones you've
mentioned, copper glycinate, manganese glycinate and molybdenum
glycinate, and others, such as chelated forms of calcium, zinc, and
chromium.) However, this should be weighed against the added cost of
"Are chelated minerals better?... In theory, a chelated mineral may be
better absorbed because it is protected from binders in food. In
practice however, it may not be worth the extra cost. Chelated calcium
is 5-10% better absorbed but costs five times as much."
Women Today Magazine: How to Choose the Right Vitamins and Supplements
"Are chelated compounds better than other forms of minerals -- such as
carbonates or citrates or ascorbates? For some minerals, a chelated
compound is better than some other forms. For some it is similar or
worse and therefore a waste of money.
What are the other kinds of molecules or compounds -- and their
implications for bioavailability? All of the minerals are different
and individual. Both calcium and magnesium are examples where
'chelated forms' are very little if any better absorbed. Inorganic
compounds of both calcium and magnesium, say calcium carbonate and
magnesium oxide, are easily separated and the calcium and magnesium
ions are well absorbed -- unless you are aged or otherwise have
insufficient stomach acids (or take antacids every time you eat)."
Supplement Quality: Are chelated minerals better than other kinds?
"Don't pay extra for 'chelated' minerals, which have been combined
with proteins. Proponents claim that the process promotes absorption,
and it does, but minimally. A better idea is to take your supplements
with meals, which also improves absorbability."
Mother Jones: To B-3 or not to B-3
All in all, I would advise that you take claims regarding the
superiority of chelated minerals with a metaphorical grain of salt.
Consider this advice from medical writer Michael Castleman (from the
"Mother Jones" article linked above): "Don't spend more than $10 a
month on expensive brand-name vitamins - instead, splurge on the
finest fruits and vegetables."
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