By Jesse Davis, DC
The history of chromium and the current state of knowledge of its role in human health and nutrition is an interesting and evolving one. The story revolves around its function in insulin signaling, where it “potentiates the action of insulin in vivo and in vitro” according to the National Academy of Sciences, and subsequently insulin’s role in metabolism.
Chromium is a trace mineral with an Adequate Intake (AI) ranging from 20-35 micrograms per day (for adults) set by the Institute of Medicine., Chromium deficiency symptoms in patients undergoing parenteral nutrition were the early evidence of chromium’s role in human blood glucose physiology. After long-term intravenous nutrition, the lack of chromium resulted in these patients experiencing poor blood glucose control and altered insulin sensitivity. The addition of chromium to the feeding solutions eliminated these deficits, and today chromium is a standard addition to IV nutrition.
Chromium’s impact on insulin’s activity has been studied since then due to the large and growing amount of insulin related health problems. In fact, the number of people with insulin signaling issues has been going through the roof, according to researchers.
“In 2010, the prevalence of insulin resistance among adults 20 years or older was 35% and was 50% for those aged 65 or older; this amounts to an estimated 79 million of Americans aged 20 or older with pre-diabetes.”
There has been a growing body of research into using chromium to combat insulin signaling related problems. While there have been numerous positive outcomes from trials, several reviews have found the impact inconclusive. However, more recent research has continued to emerge showing chromium’s impact on metabolic health, along with calls for more investigation into the topic. A 2013 review in the journal Obesity Reviews said the following:
“The purpose of this review was to evaluate the evidence for or against the efficacy of chromium supplementation in overweight and obese individuals…
A meta-analysis of 11 studies showed a statistically significant difference in weight loss favouring chromium over placebo…
The evidence from available RCTs shows that chromium supplementation generates statistically significant reductions in body weight.”
Another review in 2014 had the following to say:
“Chromium is an essential mineral for carbohydrate and lipid metabolism. Results of previous systematic reviews and meta-analyses of chromium supplementation and metabolic profiles in diabetes have been inconsistent. Recently, several published trials have emerged. We conducted a systematic review and meta-analysis to assess the effects on metabolic profiles and safety of chromium supplementation in diabetes mellitus … .
The available evidence suggests favourable effects of chromium supplementation on glycaemic control in patients with diabetes. Chromium monosupplement may additionally improve triglycerides and HDL-C levels. Chromium supplementation at usual doses does not increase the risk of adverse events compared with placebo.”
Currently the ability to reliably test for a deficiency of chromium in humans is difficult. There is also a lack of existing data about the amounts of chromium in various foods that can reliably estimate nutritional intake. Both of these are potential factors complicating the research in human studies. However, despite this, there are still consistently lower values of chromium in the blood of diabetic (Type II) and obese patients relative to healthy patients without these metabolic findings.
Chromium ion is found in two forms, trivalent and hexavalent chromium. The trivalent form is the relevant form in metabolic activity, while the hexavalent form is typically from industrial pollution resulting from heating. It can be readily neutralized in the right environments, but has a host of negative consequences if left to react with biological tissue, including a carcinogenic activity when inhaled. Trivalent chromium has not been found to have an adverse effect across a broad diversity of life forms even at higher concentrations. There is no set upper limit for trivalent chromium, as there has been little evidence of harm at higher levels of typical intakes.
Food Forms of Chromium*
*Guidance only, differs by season or processing methods. European Food Information Council, chromium in the diet, www.eufic.org.
Chromium, as is common with many ionic minerals, is poorly absorbed by the digestive system. Chromium has been found to be absorbed in amounts from <1% to upwards of 10% depending on the form. Organic (ie, biological) forms of chromium, including yeast-based delivery methods, have been tested to be superior in absorbability when compared to inorganic forms.
Patients that have blood sugar or insulin-sensitivity related concerns may benefit from assessment of their intake and response to dietary chromium. Chromium has been found to have a strong history of safe use and can offer a potential benefit with small downside risk per a doctor’s recommendation. Combining good food choices and proper supplementation options is a sound strategy to ensure sufficiency, and organic (vs. inorganic) options as well as yeast-based delivery methods have been found to be particularly strong in chromium supplementation absorbability.
-  Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc (2001) National Academies Press
-  Office of Dietary Supplements, Fact Sheet, Chromium, ods.od.nih.gov/factsheets/Chromium-HealthProfessional/
-  Institute of Medicine, Dietary Ref. Intake Tables, http://iom.nationalacademies.org/Activities/Nutrition/SummaryDRIs/DRI-Tables.aspx
-  Y Hua Y, et al. Molecular mechanisms of chromium in alleviating insulin resistance. J Nutr Biochem. 2012 Apr;23(4):313-9.
-  MD Althius, et al. Glucose and Insulin Responses to Chromium: a matalaysis. Am J Clin Nutr July 2002 vol. 76 no. 1 148-155.
-  I Onakpoya I, P Posadzki, E Ernst. Chromium supplementation in overweight and obesity: a systematic review and meta-analysis of randomized clinical trials. Obes Rev. 2013 Jun;14(6):496-507.
-  N Suksomboon, N Poolsup, A Yuwanakorn. Systematic review and meta-analysis of the efficacy and safety of chromium supplementation in diabetes. J Clin Pharm Ther. 2014 Jun;39(3):292-306.
-  Oregon State University, Linus Pauling Inst. Micronutrient Information Center, Chromium, http://lpi.oregonstate.edu/mic/minerals/chromium
-  S. Lewicki et al. The role of Chromium III in the organism and its possible use in diabetes and obesity treatment. Annals of Agricultural and Environmental Medicine 2014, Vol 21, No 2
-  Ore. State University, ibid.
-  European Food Information Council, chromium in the diet, www.eufic.org.
-  Annal of Ag and Env Med., ibid.