What is Chromium Picolinate?Q: What is Chromium?
A: Chromium picolinate
(Cr), element #24 on the periodic table, is an essential nutrient absolutely required for good health. It is an essential cofactor for the hormone insulin which regulates the metabolism of protein, fats and carbohydrates. Click here for a detailed summary of chromium and human health.
Q: What is the link between diabetes, insulin and chromium?
A: There is increasing data supporting the idea that inadequate chromium status may be responsible in part for some cases of impaired glucose tolerance, ’hyperglycemia, hypoglycemia, glycosuria and insulin resistance. Research confirms that patients with Type II diabetes, also known as maturity-onset diabetes or non-insulin dependent diabetes mellitus (NIDDM) demonstrate insulin resistance and are the ones most at risk for chromium deficiency and its consequences.
The evidence so far suggests that chromium strengthens insulin’s effects on the cell; in other words, it doesn’t work by stimulating the body to make more insulin, but rather chromium makes the insulin which is present function more effectively in the cells of the body. There are at least 16 controlled clinical studies which have tested specific chromium compounds in diabetics and pre-diabetics.
While three of the 16 properly designed studies showed no benefit of chromium supplementation in diabetics, 13 did show blood glucose improvements in the patients tested. For example, a recent study presented in 1995 at the annual meeting of the American College of Nutrition showed dramatic, improvements in blood sugar using less than one mg of supplemental chromium- picolinate in a group of women who developed gestational diabetes.
Q: I get confused about all the different forms of chromium on the market. Can you help me understand the differences between chromium picolinate and other forms of chromium? Which is the most active?
A: I don’t blame anyone for being confused about the different forms of chromium in the various products. I hope the following clears up some confusion.
GTF refers to Glucose Tolerance Factor which was the term originally given to an active form of chromium when it was first discovered (rat experiments) that chromium affected blood sugar control. Because the active form was isolated from yeast, it was sometimes called a yeast GTF. And for some chromium preparations, yeast is still a source for the chromium and still called yeast GTF. In the original experiments the yeast GTF was better utilized by the animals than just plain chromium as a salt such as chromium chloride.
GTF was never fully characterized, but there was a proposed composition that included up to two nicotinate molecules, hence the "polynicotinate" terminology. It was never shown for sure that in fact GTF existed as such, and today the terminology is outdated and not used much by researchers. Chromium polynicotinate, which is one form marketed today, was formulated on the supposition that the original GTF did in fact contain nicotinate molecules.
Chromium picolinate is also a well utilized form of chromium. The picolinate is complexed to the chromium and that makes it absorbed and used by the body more easily than other chromium forms. Why, we don’t really know yet, but when given to humans and compared with chromium polynicotinate or chromium chloride, Chromium Picolinate is usually the most well utilized form.
The reaction by which picolinate is complexed with chromium is known as a chelation reaction, so technically chromium picolinate is a chelated form of chromium.
There are also some amino acid chelate forms of chromium on the market. These are formed by combining one or more amino acids with the chromium in a chelation reaction. Presumably, the chelate amino acid forms of chromium are also more bioactive than just plain chromium salts. These amino acid chromium chelates are less well studied in humans than animals, but they have been used for many years in the formulation of animal feeds. I don’t know of any head to head comparisons of chromium chelates with chromium picolinate, or any other forms, in human studies.
Q: Are there any data supporting the claims that chromium can help you lose weight?
A: There are positive results from studies with four separate animal species supplemented with chromium picolinate: pigs, lambs, rats and chickens. In all of these species, there were increases in muscle mass and decreases in fat body mass. When it comes to humans, however, the evidence for a change in body composition is not quite as compelling; for example, a study done in college football players found no effect of chromium supplementation on body composition. Other human studies have found effects, and one study found an effect in women but not men, It should be noted that increasing lean body mass while decreasing the percentage of body fat-if eventually proven true for humans does not necessarily mean weight loss. Muscle tissue is heavier than fat: so some people may actually gain weight if they replace fat with significant amounts of muscle.
We must await large, well-designed studies in average populations (college football players may not represent an idea test-population in that they have higher than average muscular development to start with) to get the final answer on chromium and body composition, even though the data so far seem to hint at an effect. If chromium supplementation does turn out to be useful for people in terms of helping to build up muscle and break down fat, it will almost certainly be the result of its ability to make insulin work more efficiently.
Q: Is it safe and advisable to take chromium picolinate supplements during pregnancy or during breastfeeding?
A: The advisability of chromium supplementation beyond the currently recommended safe and adequate intake (50 - 200 micrograms per day) during pregnancy requires further evaluation. There is a net transfer of chromium from the mother to the fetus and placenta during pregnancy. That suggests an important role for chromium in fetal development and has led to the speculation that a drain on maternal chromium stores may play a role as a causative factor in gestational diabetes. www.supplementstogo.com
In a controlled pilot study, Dr. Lois Jovanovic-Peterson of the Sansum Clinic gave 4 - 8 micrograms chromium per day per kilogram of body weight. Roughly, that translates to about 400 micrograms per day for a woman with a pregnant weight of about 60 kg. A control group got matching pills without any chromium. All the women in the study, both those in the chromium supplemented and in the control groups, had the early signs of gestational diabetes by 20- 24 weeks of pregnancy.
After eight weeks of the treatments, blood glucose control and circulating insulin levels were significantly lower in the group that got the chromium supplements compared to the control group. Although the Jovanovic-Peterson study results were positive, further research is needed to assess the safety and usefulness of supplemental chromium for the prevention and treatment of gestational diabetes in large populations and to determine the effect of such supplementation on fetal outcomes. supplementstogo.com
Considering the essentiality of chromium for both the fetus and the mother, adding nutritional amounts of chromium (50 - 200 micrograms daily) to prenatal supplementation would appear safe and appropriate. However, until further controlled studies are available, the use of daily chromium supplementation higher than 200 micrograms should be considered experimental.
As for breastfeeding, there are not much data on the chromium concentration in human milk, but when estimates are combined from several research laboratories in the US and Europe, the average concentration values fall into a range of 6 to 12 micrograms per ounce. An average daily intake of breast milk by a normal health baby is about 25 ounces. Therefore, the average breastfed baby in the US is getting between 150 and 300 mcg of chromium per day without any chromium supplementation of the mother.
It appears that the mother’s normal diet does not affect her milk chromium levels on the short-term under non-supplemented conditions. One study where mothers were given a single oral chromium supplement (chromium chloride) of about 300 micrograms showed a temporary doubling of the milk chromium. There are no other published studies of that type, so we must view those results as preliminary. Furthermore, there are no published data on the effects of maternal chromium supplementation on the breastfeeding infant.
Although there are no official recommendations for chromium supplementation of breastfeeding mothers, many such mothers choose to take chromium. If so, it seems advisable to stay well within the recommended safe and adequate range of 50 to 200 micrograms per day.
Q: Is there a link between chromium supplementation and chromosomal defects?
A: The safety issue had been raised by a study published in December, 1995 which attempted to link chromosomal damage in the test tube to oral supplementation of chromium picolinate. These researchers used cultured Chinese hamster ovarian cancer cells to which they directly added unnaturally high amounts of chromium compounds, including chromium picolinate. Some of these cells showed chromosomal damage "clastogenic effects"). This was not particularly surprising, since this concentration directly applied to these cells in a test tube was 3,000 times the blood level of people who are ingesting chromium picolinate as supplements Very few essential minerals tested in this way would be found to be without toxicity; for example, merely doubling the blood concentration of the mineral calcium is fatal to humans. When tested by the Ames test (a specific test for mutagenicity) for cancer-causing potential, chromium picolinate was proven negative.
Q: What are the human dietary requirements for chromium?
A: The RDA Committee (1989) recommends 50-200 mcg of chromium/day. Data from U. S. Government sources show that the great majority of Americans get less chromium in their daily diets than the amount recommended by nutrition experts. The vast majority of Americans get less than 50 mcg/day.
Q: Are there any natural sources of dietary chromium?
A: Few foods are rich sources of chromium in the Western diet. The best food sources are organ meats, mushrooms, wheat germ, broccoli, brewer’s yeast and processed meats.
Q: How does chromium facilitate the action of insulin?
A: While trivalent chromium works with insulin to move glucose into cells, we currently do not know how many other critical actions of insulin require chromium to function. However, regarding the insulin-induced movement of glucose into cells, it is likely that chromium is either involved with the binding of insulin to its receptor (the site on the cell membrane which responds to signals from biochemical messengers such as hormones, drugs and nutrients and then stimulates or inhibits specific cellular functions) or with certain of the reactions which take place after the initial receptor site activation, reactions that are referred to as post-receptor events.
Q: At what dose does oral chromium become toxic?
A: It is extremely difficult to poison laboratory animals with oral chromium. For example, cats fed 1,000 mg of trivalent chromium per day showed no signs of toxicity (the equivalent daily dose for a 150 lb person would be approximately 35,000 mg per day or 3,5 million mcg per day. That would equal 175,000 200 mcg tablets per day for a human On March 14, 1996, a safety study conducted by the U. S. Department of Agriculture was presented at the Society of Toxicology’s annual meeting. This study looked at various supplemental doses (including none) of chromium chloride and chromium picolinate fed to rats for 6 months, The highest doses were equal to a human consuming 5,000 tablets of 200 micrograms chromium picolinate. At regular intervals during the study the rats were weighed and blood was taken for laboratory tests. At the end of the study the livers and kidneys (organs that would have the highest tissue levels of chromium) were examined under the microscope. There were no differences in any of the measurements or examinations between the various groups. The investigators were blinded as to which group the animals were in when the measurements and evaluations were performed.
Q: What are the main areas of ongoing research with chromium?
A: Insulin metabolism continues to be a major area of chromium research. In addition, studies are ongoing assessing chromium’s possible effects on essential hypertension, cellular immunity and calcium/bone metabolism. Human studies are also underway evaluating chromium compounds value as an adjunct to exercise for weight loss.