Chromium
What is chromium?
This essential mineral, required by the body in
trace amounts, was first discovered in 1797 by a chemist in France named Louis-
Nicolas Vaquelin. Many years later, a physician and research scientist in the
U.S. named Walter Mertz, discovered that chromium played a key role in
carbohydrate metabolism, possibly by participating in formation of a special
compound which he named "glucose tolerance factor," or GTF.
glucose tolerance factor include
Ø
chromium (which may be the most active
component).
Ø
nicotinic acid (a version of
vitamin B3).
Ø
amino acids that make up glutathione (glutamic acid,
cysteine, and glycine).
What Chromium Does:
Ø Aids in the control and production of insulin
Ø Aids in the metabolism of carbohydrates, fats and
proteins
Ø Chromium picolinate increases fat loss and lean
muscle tissue gain
Ø Controls levels of cholesterol in the blood
Ø Improves glucose tolerance in people with turner’s
syndrome
Ø Increases general resistance to infection
Ø Needed for energy
Ø Regulator of blood sugar
Ø Stimulates the synthesis of proteins in the body
Ø Suppresses hunger pains
What can high-chromium foods do for you?
Help maintain normal blood sugar and insulin levels
Support normal cholesterol levels
What is the function of chromium?
1-Controlling blood sugar levels
Ø As the active component of glucose tolerance
factor(GTF), chromium plays a fundamental role in controlling blood sugar
levels. The primary function of GTF is to increase the action of insulin.
Insulin is the hormone responsible for carrying sugar (glucose) into the cells
where it can be used for energy.
Ø After a
meal, blood glucose levels begin to rise, and, in response, the pancreas
secretes insulin. Insulin lowers blood glucose levels by increasing the rate in
which glucose enters the cells. To accomplish this, insulin must be able to
attach to receptors on the surface of cells. GTF is believed to initiate the
attachement of insullin to the insulin receptor.
2-Metabolizing cholesterol & nucleic acid
Ø Chromium
may also participate in cholesterol metabolism, suggesting a role for this
mineral in maintaining normal blood cholesterol levels. In addition, chromium
is involved in nucleic acid metabolism. Nucleic acids are the building blocks
of DNA, the genetic material found in every cell.
supplemental Cr as Cr
picolinate improved the blood glucose, insulin, cholesterol, hemoglobin A1C in people with Type 2 DM
Absorption occurs passively and possibly actively
in the small intestine.
Since only 0.5-3% are absorbed, accompanying food
components are highly significant:
Aminoacids, ascorbate, and oxalate enhance
absorption;
Phytate and zinc are said to impair chromium
uptake.
In the blood chromium is bound to transferrin;
when transferrin is saturated with Fe, chromium can bind to other proteins
nonspecifically.
excretion
is predominantly renal; controlled reabsorption may occur.
What health conditions require special emphasis on
chromium?
Ø
Acne
Ø
Glaucoma
Ø
High cholesterol levels
Ø
High triglyceride levels
Ø
Hypoglycemia
Ø
Obesity
Ø
Psoriasis
Ø
Type 2 diabetes
Signs of Chromium Deficiency:
Anxiety |
Aortic cholesterol plaque |
Attention deficit disorder |
Bipolar disease |
Coronary blood vessel disease |
Decreased sperm count |
Depression |
Dr. Jekyll/Mr. Hyde rages |
Elevated blood cholesterol |
Elevated blood triglycerides |
Fatigue |
Glucose intolerance (particularly in people with diabetes) |
Hyperactivity |
Hyper-insulinemia |
Hyper-irritability |
Hypoglycemia |
Impaired growth |
Inadequate metabolism of amino acids |
Increased risk of arteriosclerosis |
Infertility |
Learning disabilities |
Negative nitrogen balance |
Obesity |
Peripheral neuropathy |
Pre-diabetes and diabetes |
|
Using Food Combining to Enhance Chromium Benefits
Ø
Vitamin C and Niacin are two
powerhouses when it comes to chromium enhancement.
Foods high in Vitamin C power include: fruit juices, fruits & vegetables.
Foods high in Niacin power include: meats including poultry & fish, and whole
grains. Checking food labels can assist greatly in the Vitamin C/Niacin search.
What are deficiency symptoms for chromium?
Ø
Chromium deficiency leads to insulin resistance, a condition in which the
cells of the body do not respond to the presence of insulin. Insulin resistance
can lead to elevated blood levels of insulin (hyperinsulinemia) and elevated
blood levels of glucose, which can ultimately cause heart disease and/or
diabetes.
What are deficiency symptoms for chromium?
Ø
In fact, even mild dietary deficiency of chromium is associated with a
medical condition known as Syndrome X. Syndrome X represents a constellation of
symptoms, including hyperinsulinemia, high blood pressure, high triglyceride
levels, high blood sugar levels, and low HDL cholesterol levels, that increase
one's risk for heart disease.
factors might contribute to a
deficiency of chromium?
Ø
If you have diabetes or heart disease, the amount of chromium your body
needs may be increased. You may also need extra chromium if you experience
physical injury or trauma or mental stress. All of these conditions increase
the excretion of chromium. But in addition, in the case of stress, the need for
increased chromium may relate directly to blood sugar imbalance.
What events can indicate a need for more
high-chromium foods?
Hyperinsulinemia (elevated blood levels of insulin)
High blood pressure
High triglyceride levels
High blood sugar levels
High cholesterol levels
Insulin resistance
Low HDL cholesterol
What are toxicity symptoms for chromium?
In 2001, the Institute of Medicine at the National
Academy of Sciences conducted a thorough review of the chromium research and
concluded that excessive intake of chromium from foods or supplements is not
associated with any adverse effects. As a result, no Tolerable Upper Intake
Level (UL) was established for this mineral. However, the Institute of Medicine
noted that people with liver or kidney disease may be more susceptible to
adverse effects from excessive intake of chromium, and cautioned such individuals
to avoid taking chromium supplements in higher than recommended amounts.
GTF is supposed to enhance the effects of insulin
In the target cells and thereby enhance glucose
uptake.
It was also hypothesized that Cr has direct
influence on the pancreas.
The mechanism of action
Ø
The mechanism of action of Cr involves increased insulin binding,
increased insulin receptor number, and increased insulin receptor
phosphorylation
Drug-Nutrient Interactions
What medications affect chromium?
Ø
Chromium supplementation can cause blood sugar levels to drop. If you are
taking insulin or an oral glucose-lowering medication (for example, Diabeta or
Micronase), be sure to consult your physician before taking chromium
supplements, as you may need to decrease your current dose of medication to
prevent your blood sugar levels from decreasing too much.
Ø
Calcium carbonate, found in calcium supplements and antacids, decreases
the absorption of chromium, while aspirin is believed to increase chromium
absorption.
Chromium supplements may interact with medications
by increase or decrease absorption
Medication |
Nature of interaction |
Antacids Corticosteroids H2 Blockers (such as cimetidine, famotidine, nizatidine,
and rantidine) Proton-Pump Inhibitors (such as omeprazole, lansoprazole,
rabeprazole, pantoprazole, and esomeprazole) |
Antacids, Corticosteroids, H2 Blockers and Proton-Pump
Inhibitors alter stomach acidity and may impair chromium absorption and/or
enhance excretion |
Beta-Blockers (such as atenolol or propanolol) Corticosteroids Insulin Nicotinic Acid Nonsteroidal Anti-Inflammatory drugs (NSAIDS) Prostaglandin Inhibitors (such as ibuprofen, indomethacin,
naproxen, piroxicam, and aspirin) |
Beta-blockers, Corticosteroids, Insulin, Nicotinic Acid,
Nonsteroidal Anti-Inflammatory Drugs and Prostaglandin Inhibitors may produce
enhanced effects when taken with chromium and/or increase chromium |
Nutrient Interactions
How do other nutrients interact with chromium?
Ø
Diets high in simple sugars increase the urinary excretion of chromium
and rob the body of some of the chromium it needs. Diets rich in whole grains
can also decrease absorption of chromium, since whole grains contain a compound
called phytic acid, which can bind to chromium, form an insoluble complex, and
prevent it from being absorbed.
Ø
Whole grains, however, contain significant amounts of chromium, and the
activity of phytic acid in grains does not prevent us from getting chromium
from whole grain foods. As a result, a diet rich in whole grains is still
unlikely to increase our risk of chromium deficiency.
Ø
Ascorbic acid (vitamin C) increases the absorption of chromium.
What foods provide chromium?
Ø The amount of chromium in most foods is minimal -
less than 2 mcg's (micrograms) per serving.
Ø Good sources of chromium include meats, whole
grains, fruits, vegetables and some spices.
Ø
lettuce as an excellent source of chromium and onions and tomatoes as
very good sources, the following foods are also believed to provide a
significant amount of chromium: brewer's yeast, oysters, liver, whole
grains, bran cereals, and potatoes. Beer and wine can accumulate
chromium during fermentation.
Ø Foods containing simple sugars such as fructose
and sucrose tend to be low in chromium.
Ø
food processing methods often remove the naturally occurring chromium. As
a result, obtaining a sufficient amount of chromium in the diet can be
difficult.
Best Food Sources Containing Chromium
Chromium (mcg |
Foods High in Chromium |
3 |
Potatoes, mashed, 1 cup |
3 |
Garlic, dried, 1 teaspoon |
4 |
English Muffin, whole |
8 |
Grape Juice, 1 cup |
11 |
Broccoli, ½ cup |
Food Sources of Chromium:
Beef |
Beer (some brands) |
Black strap molasses |
Brewer’s yeast |
Brown rice |
Calves’ liver |
Cereals |
Cheese |
Chicken breast |
Chicken legs |
Corn and corn oil |
|
Dairy products |
Dried beans |
Dulse |
Eggs |
Fish and seafood |
Fresh fruit |
Fresh vegetables |
Meat |
Mushrooms |
Potatoes with skin |
Whole grains and bread |
|
Herb Sources of Chromium:
Catnip |
Horsetail |
Licorice |
Nettle |
Oat straw |
Red clover |
Sarsaparilla |
Wild yam |
Yarrow |
Pharmaceutial forms
Ø
EVE tab. ( chromium 25mcg)
prenatal tab
Ø
chromax cap (100mcg)
Recommended Chromium Daily Intake
Chromium
supplement doses generally range from 50 mcg to 200 mcg per day.
Ø Males - Daily Recommended Chromium Intake:
Ø Males age 19-50 require 35 mcg of chromium per
day.
Ø
Males over 50 require 30 mcg of chromium per day.
Ø Females - Daily Recommended Chromium Intake:
Ø Females age 19-50 require 25 mcg of chromium per
day.
Ø Females over 50 require 20 mcg of chromium per
day.
people with more overt impairments in glucose tolerance and
diabetes usually require more than 200 µg/day. Daily intake of 8 µg of Cr per
kg body weight was also more effective than 4 µg/kg in women with gestational
diabetes.
The Adequate Intake (AI) levels for chromium, set
in 2001 by the Institute of Medicine at the National Academy of Sciences are as
follows:
0-6 months: .2 micrograms |
7-12 months: 5.5 micrograms |
1-3 years: 11 micrograms |
4-8 years: 15 micrograms |
Boys 9-13 years: 25 micrograms |
Girls 9-13 years: 21 micrograms |
Boys 14-18 years: 35 micrograms |
Girls 14-18 years: 24 micrograms |
Men 19-30 years: 35 micrograms |
Women 19-30 years: 25 micrograms |
Men 31-50 years: 35 micrograms |
Women 31-50 years: 25 micrograms |
Men 51-70 years: 30 micrograms |
Women 51-70 years: 20 micrograms |
Men greater than 70 years: 30 micrograms |
Women greater than 70 years: 20 micrograms |
Pregnant women 14-18 years: 29 micrograms |
Pregnant women 19-50 years: 30 micrograms |
Lactating women 14-18 years: 44 micrograms |
Lactating women 19-50 years: 45 micrograms |
|
Impact of Cooking, Storage and Processing
How do cooking, storage, or processing affect chromium?
Ø
Under most circumstances, food processing methods decrease the chromium
content of foods. For example, chromium naturally occurs in the bran and germ
of whole grains. When whole grains are milled to make flour, the germ and bran
are removed, and consequently most of the chromium is lost. Also, the
refinement of sugar cane and sugar beets to make sugar (sucrose) removes most
of the chromium that naturally occurs in the plants.
Ø
On the other hand, acidic foods cooked in stainless steel cookware can
accumulate chromium by leaching the mineral from the cookware.
The admi. Of supplementary chromium 150 mcg daily
for 2 months resulted in the normalization of impaired glucose tolerance in
four of eight nondiabetic subjects and some benefit in most of the others (
J.Am.med.Ass.,1968,206,36. criticisms of the use of chromium trichloride in
diabetes)
Chromium Loss Within the Body, Including Chromium
Deficiency
Ø
It's important to note that chromium deficiencies in humans are rare.
However, the following conditions can create a situation in which chromium is
secreted or lost from the body: pregnancy, physical trauma, extreme stress, a
diet high in simple sugars, excessive exercise, and infection.
Ø
A chromium deficiency is difficult to diagnose because medical tests
involving blood, urine and hair levels are not reflective of the amount of
chromium that may be currently stored within the body.
Monitoring excessive human exposure
Ø
Overexposure to chromium can occur in welders and other workers in the
metallurgical industry, persons taking chromium-containing dietary supplements,
patients who have received metallic surgical implants and individuals who
accidentally or intentionally ingest chromium salts. Chromium concentrations in
whole blood, plasma, serum or urine may be measured to monitor for safety in
exposed workers, to confirm the diagnosis in potential poisoning victims or to
assist in the forensic investigation in a case of fatal overdosage
chromium Picolinate
Ø
Studies suggest that the biochemical, physiological, and behavioral
actions of chromium picolinate may be a consequence of the effects of picolinic
acid on the central nervous system. Analogues of picolinic acid have been shown
to induce profound alterations in the metabolism of serotonin, dopamine, and
norepnephrine in brain. Thus, caution should be used with chromium picolinate
supplements especially by individuals prone to behavioral disorders.
There are several forms of chromium available in dietary supplements? :
Chromium picolinate
Chromium polynicotinate
Chromium chloride
Chromium-enriched yeast
What is Chromium Picolinate
Ø
Chromium picolinate is a combination of the trace
Ø
mineral chromium and picolinate acid.
Ø
• Chromium is a naturally-occurring trace mineral
Ø
found in common foods such as brewers yeast,
Ø
baked beans, whole grains, etc.
Ø
• Picolinate acid simply aids in the absorption ofchromium.
How does Chromium Picolinate work
It is speculated that chromium picolinate works by
stimulating the activity of insulin.
Ø
Insulin helps to transport glucose to the body’s cells in order to
provide energy.
Ø
The exact mechanisms by which chromium improves insulin efficiency is
unclear.
Caution & Comments About Chromium
Ø
Chromium is bound up into indigestible forms when it meets up the
phosphates in milk
Ø
Chromium is sometimes called glucose tolerance factor or gtf
Ø
High levels of sugars in the diet cause chromium to be excreted through
the kidneys
Ø
If you develop a rash, either try switching brands or discontinue use
Ø
If you feel lightheaded, stop taking the supplement and consult your
health care provider.
Ø
If you have diabetes, do not take supplemental chromium
(especially chromium picolinate) without first consulting with a qualified
health care provider.
Ø
Incidence of diabetes and heart disease decreases with increased levels
of chromium in the body
Ø
Some people experience lightheadedness or a slight skin rash when taking
chromium.
Ø
There is no evidence that chromium is toxic, even in high doses, since
any excess is excreted. However, it is suggested that you do not take
more than 200 mcg daily unless supervised by a registered practitioner.
Ø
Vitamin C increases the absorption of chromium
Ø
White flour and white sugar steals chromium by stepping up insulin
production, which in turn flushes out chromium.
Chromium &
Diabetes
Ø
In Type 2 Diabetes, when a chromium deficiency is involved, the body's
ability to utilize glucose to meet energy needs is impaired.
Chromium & Blood
Lipid Levels
Ø
Although the effects of chromium supplements remain inconclusive, some
studies involving 150 mcg to 1,000 mcg of daily chromium supplementation
resulted in a decrease in LDL cholesterol (commonly referred to as bad
cholesterol), with increases in HDL (good) cholesterol levels
Chromium &
Weight Loss
Ø
Claims exist that chromium can reduce fat in the body while increasing
lean muscle mass.
Precautions
Ø Because of the specific transport mechanisms, only
limited amounts of chromium(III) enter the cells. Several in vitro studies indicated
that high concentrations of chromium(III) in the cell can lead to DNA damage. Acute
oral toxicity ranges between 1500 and 3300 µg/kg. The proposed beneficial
effects of chromium(III) and the use as dietary supplements yielded some
controversial results, but recent reviews suggest that moderate uptake of
chromium(III) through dietary supplements poses no risk.
Claims
Chromium Picolinate will:
Ø “Reduce body fat”
Ø “Retain and
build lean muscle”
Ø “Reduce
cholesterol levels”
Ø “Helps
control hunger”
Ø “Melt fat
away”
In Summary
Ø
Although there is no doubt that the mineral chromium is vital to the
overall health of the body, much controversy remains as to the validity
surrounding chromium supplements and the degree of their healthy benefits
to the human body.
Ø
The best source for chromium remains in the consumption of foods high in
chromium such as broccoli and grape juice.
Ø
In general, women tend to consume ample levels of chromium in their daily
diet while men consume below-minimum levels in their daily diet. Given such, by
opting for foods rich in the mineral chromium, men may achieve health benefits
Referances
Ø
Pizzorno: Textbook of Natural Medicine, 2nd ed., pg 1436
Ø
Mertz W. Chromium in human nutritiona: a review. J Nutr 1993; 123:
626–633
Ø
Brody_ Nutritional Biochemistry
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