Chromium deficiency
Encyclopedia
Chromium deficiency is a disorder that results from an insufficient dietary intake of chromium
. Whether or not such a deficiency ever occurs in people eating a normal diet is debated, and clear cases of deficiency have only been observed in hospital patients who were fed defined liquid diets intravenously for long periods of time. Although chromium is an essential trace element
in humans, the basis for this need is not fully understood, since no chromium-containing biomolecules with beneficial effects have been characterized.
Approximately 2% of ingested chromium(III) is absorbed, with the remainder being excreted in the feces. Amino acids, vitamin C and niacin may enhance the uptake of chromium from the intestinal tract. After absorption, this metal accumulates in the liver, bone, and spleen.
Trivalent chromium is found in a wide range of foods, including: whole-grain products, processed meats, high-bran breakfast cereals, coffee, nuts, green beans, broccoli, spices, and some brands of wine and beer. Most fruits and vegetables and dairy products only contain low amounts. Most of the chromium in people's diet comes from processing or storing food in pans and cans made of stainless steel
, which can contain up to 18% chromium.
The amount of chromium in the body can be decreased as a result of a diet high in simple sugars, which increases the excretion of the metal through urine. Because of the high excretion rates and the very low absorption rates of most forms of chromium, acute toxicity
is uncommon.
are severely impaired glucose tolerance
, a loss of weight, and confusion. Another patient also developed nerve damage (peripheral neuropathy
).
Chromium picolinate is the most commonly used synthetic supplement. However, recent studies "have concluded that such supplements have no demonstrated effects on healthy individuals." A meta-analysis
in 2002 found no effect on blood glucose
or insulin
in healthy people, and the data were inconclusive for diabetics. Subsequent trials gave mixed results, with one finding no effect in people with impaired glucose tolerance, but another seeing a small improvement in glucose resistance. In a 2007 review of these and other clinical trials it was again concluded that chromium supplements had no beneficial effect on healthy people, but that there might be an improvement in glucose metabolism in diabetics, although the authors stated that the evidence for this effect remains weak.
A 2003 pilot trial of 15 patients suggested that chromium picolinate might have antidepressant effects in atypical depression
. A larger trial in 2005 set up to test this finding found no effect on depression in its test group, but suggested that the use of chromium supplementation could help to reduce carbohydrate cravings and regulate appetite in these patients. A post-hoc analysis
of a subpopulation of patients in this study that experienced high carbohydrate cravings suggested that these patients experienced significant improvements in their depression compared to those treated with a placebo.
This supplement is purported to correct imbalances in glucose metabolism due to chromium deficiency, even though the occurrence of such a deficiency is extremely rare in countries where the supplement is sold. The mechanism by which this complex enters the cells in the body differs from that for the introduction of trivalent chromium found naturally in food does, and for this reason the safety of this supplement is debatable, since chromium is toxic at high levels.
Although it is controversial if supplements should be taken by healthy adults eating a normal diet, chromium is needed as a component of the defined liquid diet that is given to patients receiving total parenteral nutrition
(TPN), since deficiency can occur after many months of this highly restricted diet. As a result chromium is added to normal TPN solutions, although the trace amounts from even in supposedly "chromium free" preparations may be enough to prevent deficiency in some individuals. Indeed, a 1992 paper in The Lancet
suggested that adding chromium to feeding solutions given to children produces excessive levels of this metal in their bodies.
Chromium
Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable...
. Whether or not such a deficiency ever occurs in people eating a normal diet is debated, and clear cases of deficiency have only been observed in hospital patients who were fed defined liquid diets intravenously for long periods of time. Although chromium is an essential trace element
Trace element
In analytical chemistry, a trace element is an element in a sample that has an average concentration of less than 100 parts per million measured in atomic count, or less than 100 micrograms per gram....
in humans, the basis for this need is not fully understood, since no chromium-containing biomolecules with beneficial effects have been characterized.
Dietary guidelines
The US dietary guidelines for adequate daily chromium intake were lowered in 2001 from 50–200 µg for an adult to 30–35 µg (adult male) and to 20–25 µg (adult female). These amounts were set to be the same as the average amounts consumed by healthy individuals. Consequently, it is thought that few Americans are chromium deficient.Approximately 2% of ingested chromium(III) is absorbed, with the remainder being excreted in the feces. Amino acids, vitamin C and niacin may enhance the uptake of chromium from the intestinal tract. After absorption, this metal accumulates in the liver, bone, and spleen.
Trivalent chromium is found in a wide range of foods, including: whole-grain products, processed meats, high-bran breakfast cereals, coffee, nuts, green beans, broccoli, spices, and some brands of wine and beer. Most fruits and vegetables and dairy products only contain low amounts. Most of the chromium in people's diet comes from processing or storing food in pans and cans made of stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....
, which can contain up to 18% chromium.
The amount of chromium in the body can be decreased as a result of a diet high in simple sugars, which increases the excretion of the metal through urine. Because of the high excretion rates and the very low absorption rates of most forms of chromium, acute toxicity
Acute toxicity
Acute toxicity describes the adverse effects of a substance that result either from a single exposure or from multiple exposures in a short space of time...
is uncommon.
Symptoms
The symptoms of chromium deficiency caused by long-term total parenteral nutritionTotal parenteral nutrition
Parenteral nutrition is feeding a person intravenously, bypassing the usual process of eating and digestion. The person receives nutritional formulae that contain nutrients such as glucose, amino acids, lipids and added vitamins and dietary minerals...
are severely impaired glucose tolerance
Impaired glucose tolerance
Impaired glucose tolerance is a pre-diabetic state of dysglycemia that is associated with insulin resistance and increased risk of cardiovascular pathology. IGT may precede type 2 diabetes mellitus by many years...
, a loss of weight, and confusion. Another patient also developed nerve damage (peripheral neuropathy
Peripheral neuropathy
Peripheral neuropathy is the term for damage to nerves of the peripheral nervous system, which may be caused either by diseases of or trauma to the nerve or the side-effects of systemic illness....
).
Supplementation
Meta-analysis
In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. In its simplest form, this is normally by identification of a common measure of effect size, for which a weighted average might be the output of a meta-analyses. Here the...
in 2002 found no effect on blood glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
or insulin
Insulin
Insulin is a hormone central to regulating carbohydrate and fat metabolism in the body. Insulin causes cells in the liver, muscle, and fat tissue to take up glucose from the blood, storing it as glycogen in the liver and muscle....
in healthy people, and the data were inconclusive for diabetics. Subsequent trials gave mixed results, with one finding no effect in people with impaired glucose tolerance, but another seeing a small improvement in glucose resistance. In a 2007 review of these and other clinical trials it was again concluded that chromium supplements had no beneficial effect on healthy people, but that there might be an improvement in glucose metabolism in diabetics, although the authors stated that the evidence for this effect remains weak.
A 2003 pilot trial of 15 patients suggested that chromium picolinate might have antidepressant effects in atypical depression
Atypical depression
Atypical depression is a subtype of dysthymia and major depression, sharing many of the symptoms of both, but also being characterized by mood reactivity—being able to experience improved mood in response to positive events. In contrast, sufferers of "melancholic" depression generally cannot...
. A larger trial in 2005 set up to test this finding found no effect on depression in its test group, but suggested that the use of chromium supplementation could help to reduce carbohydrate cravings and regulate appetite in these patients. A post-hoc analysis
Post-hoc analysis
Post-hoc analysis , in the context of design and analysis of experiments, refers to looking at the data—after the experiment has concluded—for patterns that were not specified a priori. It is sometimes called by critics data dredging to evoke the sense that the more one looks the more likely...
of a subpopulation of patients in this study that experienced high carbohydrate cravings suggested that these patients experienced significant improvements in their depression compared to those treated with a placebo.
This supplement is purported to correct imbalances in glucose metabolism due to chromium deficiency, even though the occurrence of such a deficiency is extremely rare in countries where the supplement is sold. The mechanism by which this complex enters the cells in the body differs from that for the introduction of trivalent chromium found naturally in food does, and for this reason the safety of this supplement is debatable, since chromium is toxic at high levels.
Although it is controversial if supplements should be taken by healthy adults eating a normal diet, chromium is needed as a component of the defined liquid diet that is given to patients receiving total parenteral nutrition
Total parenteral nutrition
Parenteral nutrition is feeding a person intravenously, bypassing the usual process of eating and digestion. The person receives nutritional formulae that contain nutrients such as glucose, amino acids, lipids and added vitamins and dietary minerals...
(TPN), since deficiency can occur after many months of this highly restricted diet. As a result chromium is added to normal TPN solutions, although the trace amounts from even in supposedly "chromium free" preparations may be enough to prevent deficiency in some individuals. Indeed, a 1992 paper in The Lancet
The Lancet
The Lancet is a weekly peer-reviewed general medical journal. It is one of the world's best known, oldest, and most respected general medical journals...
suggested that adding chromium to feeding solutions given to children produces excessive levels of this metal in their bodies.
Further reading
- Journal of the American College of Nutrition, Vol 4, Issue 1 107-120, Copyright © 1985 by American College of Nutrition
- http://ods.od.nih.gov/factsheets/chromium.asp