By Dr Malcolm Ball
Recently science has begun to understand the role that the essential nutrient chromium plays in cellular metabolism and the benefits that ensuring sufficient chromium in our diets may have – particularly in those people who suffer from glucose intolerance.
Chromium is an essential mineral found in trace amounts in many foods and plays an instrumental part in how the body regulates insulin activity. When you digest a meal the first stage of metabolism is for the nutrients including glucose to enter the blood, this causes an increase in blood glucose levels and under normal circumstances induces an increase in the amount of insulin to make use of this new fuel. As the fuel (glucose) is used in the cell blood sugar lowers and hormones are released making us hungry. If this drop is too fast then it may lead to a sugar craving(1)
The primary function of insulin in metabolism is to signal to a cell to allow glucose to enter. This glucose is then either used immediately as fuel or packaged up to be ultimately stored as fat. Recent Research has shown, however, that insulin does not act alone to make this happen and that a cofactor known as chromodulin requires the biologically active forms of trivalent chromium (which is the kind of chromium that can be found in food) to assist insulin lower plasma glucose levels (2). Chromodulin acts to enhance insulin binding, which creates a much stronger signal for the cell to internalise glucose making energy use more efficient and blood glucose return to fasting levels more quickly (3). What does this mean to us as a whole? Essentially, without sufficient chromium to activate chromodulin excess insulin is needed to get the job done that may ultimately result in insulin insensitivity (4). In other words it doesn’t matter how much insulin you have, whether it be your own or being taken externally, if you don’t have enough chromium in your diet things just aren’t working the way they should.
While it is clear that chromium is necessary for our metabolism to function properly, studies show that it is difficult to consume the recommended amount of chromium in a modern-day diet (see: https://www.nrv.gov.au/nutrients/chromium and http://ods.od.nih.gov/factsheets/Chromium-HealthProfessional/) as highly processed foods tend to destroy chromium in its bioavailable form. . Additionally it has been shown that chromium does not have a high residence time in the body and is actively excreted when it has done its job (5) this means that diets high in simple sugars and carbohydrates (as can be found in fruits, junk food) can cause the body to expel chromium faster.
While it is well established that chromium is important for good health much is still not fully understood and there is controversy as to the effectiveness of artificial supplements in treating insulin resistance (2, 6). Part of the problem arises from the fact that there is no conclusive test for chromium deficiency (while some might argue that insulin resistance is a de-facto test for chromium deficiency) and so evidence of benefit is based upon the question “was a positive result was observed with supplementation?”. To date there have been studies that have resulted in both a yes and a no to this question, however two pieces of evidence are telling: 1) firstly artificial supplements have been shown to be very poorly absorbed, and may in fact damage health (7, 8) and the results using organic (and often food based) sources of chromium were effective (9). It is therefore generally agreed that the most effective way to generate and maintain healthy levels of chromium is by ingesting foods rich in the mineral itself. Foods including processed meats, whole-grain products, broccoli, nuts and eggs, as well as foods sourced from the mega grasses such as sugarcane, continue to be the most effective way of taking in chromium and the best chance of maintaining equilibrium within the body (see: http://ods.od.nih.gov/factsheets/Chromium-HealthProfessional/ for a list of chromium rich foods).
Research has also linked chromium to a number of other metabolic functions such as lipid metabolism (10) and scientist are still working hard to find ways of measuring chromium deficiencies and determine the best way to fight against metabolic disorders linked to nutrient deficiencies such as Type 2 diabetes, metabolic syndrome, and various cardiovascular diseases.
The body needs chromium in order to manage insulin, which in turn influences blood glucose. Without chromium, the human body is essentially running like a car without an engine valve or fuel pump – you may putter along for a while but you are not operating at a fully functioning level. Unfortunately, we don’t have dashboard lights to alert us to when we are running low on nutrients – we have to rely on our internal systems and monitor our diet to ensure chromium intake.
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Racek J, Sindberg CD, Moesgaard S, Mainz J, Fabry J, Muller L, et al. Effect of chromium-enriched yeast on fasting plasma glucose, glycated haemoglobin and serum lipid levels in patients with type 2 diabetes mellitus treated with insulin. Biological trace element research. 2013;155(1):1-4.
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