The study looked at the effect of the commercially available Diachrome supplement (Nutrition 21) on the glycaemic control and blood lipids of 36 overweight or obese people with type 2 diabetes.
Writing in the journal Diabetes Technology and Therapeutics, lead author Gregory Singer said: "This pilot study demonstrates that supplementation with a combination of chromium picolinate and biotin in poorly controlled patients with diabetes receiving antidiabetic therapy improved glucose management and several lipid measurements."
"Chromium picolinate /biotin supplementation may represent an effectuive adjunctive nutritional therapy to people with poorly controlled diabetes with the potential for improving lipid metabolism."
Chromium is an essential trace mineral that occurs naturally in small amounts in some foods, including brewer's yeast, lean meat, cheese, pork kidney and whole grain bread and cereals. It is poorly absorbed by the human body but is known to play an important role in the metabolism of carbohydrate, fat and protein.
A study presented at a meeting of the Federation of American Societies for Experimental Biology in San Diego in April 2005 indicated that chromium picolinate is better absorbed by humans than other forms of the mineral.
The new placebo-controlled, double-blinded trial randomised 36 overweight and obese people (BMI of between 25 and 35 kg per sq. m, age range 18-65) with impaired glucose control (two-hour blood glucose measures of greater than 200 mg per decilitre) to receive either the Diachrome supplement (600 micrograms of chromium picolinate, 2 mg biotin) or placebo (dicalcium phosphate) for 30 days. Subjects continued to receive oral anti-diabetic drug(s)
At the end of the study, authors Singer and Jeff Geohas report that the average blood glucose levels after eating, measured as the area under the curve (AUC), improved as a result of the chromium picolinate, biotin supplementation, with a reduction of 9.7 per cent. However, the average AUC for the placebo group increased by 5.1 per cent.
Another measure of diabetic control - fructosamine levels - were also found to improve as a result of the Diachrome supplements, with a measured reduction of 1.3 millimoles per litre of serum. Levels increased in the placebo group by 0.7 millimoles per litre of serum.
Improvements in blood lipid levels are also reported by Singer and Geohas, with a non-significant decrease in total cholesterol levels (six per cent) as a result of the supplement. Significant differences between the placebo and intervention groups' triglyceride levels were observed, with a decrease of 9.25 milligrams per decilitre reported for the chromium picolinate, biotin supplemented group, and an increase of 59.75 mg per dL for placebo.
"Results from this pilot study promote the potential benefits of supplementing chromium picolinate and biotin with one's daily diabetes care regimen," said Singer. "Chromium picolinate with biotin represents an adjunctive strategy to conventional oral diabetes therapy for improved blood sugar control and cholesterol metabolism."
"Additional research currently underway may provide us with further understanding of the supplement's role in the management of type 2 diabetes," he said.
The researchers also noted that the safety of both chromium picolinate and biotin has been established and that both are generally recognised as safe (GRAS).
The mechanism behind the effects was not investigated by the researchers, but an in vivo study published last year in the Journal of Nutrition (Vol 136, pp. 415-420) reported that chromium may help muscle cell insulin-receptor sites to bind insulin. Once the insulin is bound, the cell can then activate "glucose transporters" to take glucose up from the blood, helping to metabolize glucose at a steady rate, leading to greater glucose control.
An estimated 39m people are affected by diabetes in the US and EU 25. The total costs in the US alone are thought to be as much as $132bn, with $92bn being direct costs from medication, according to 2002 American Diabetes Association figures.
Source: Diabetes Technology and Therapeutics Volume 8, Number 6, Pages 636-643 "The effect of chromium picolinate and biotin supplementation on glycaemic control in poorly controlled patients with type-2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial" Authors: G.M. Singer, J. Geohas