"The results further support that chromium may serve as a safe and effective adjunct to medication in helping people with type-2 diabetes improve their blood sugar control. In patients who take sulfonylurea to control elevated blood sugar, weight gain is common. However, the study findings show that weight gain was less with use of supplemental chromium," said researcher, William Cefalu.
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 last April indicated that chromium picolinate is better absorbed by humans than other forms of the mineral.
The new randomised, double-blind, placebo-controlled study, led by Julie Martin from the University of Vermont, significantly adds to the positive results linking chromium supplementation and diabetes reported in other trials.
Two-thirds of people with type-2 diabetes are estimated to not be at the suggested goal for their blood sugar. Moreover, over 80 per cent of type-2 diabetics are overweight, significantly increasing their risk of disease-related complications, including cardiovascular disease, which is the leading cause of death amongst patients with diabetes.
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.
The study, published in the August issue of the journal Diabetes Care (Vol. 29, pp. 1826-1832), recruited 27 type-2 diabetics and prescribed them to receive the anti-diabetic medication, sulfonylurea (glipizide gastrointestinal therapeutic system 5 mg/day) with placebo (sugar) for three months. Subjects were then to receive either the sulfonylurea plus placebo (12 subjects) or the sulfonylurea plus 1,000 micrograms of chromium picolinate (17 subjects) for a further six months.
The chromium picolinate was provided by Nutrition 21 (Chromax).
Body composition, insulin sensitivity, and glycemic control were measured at the start of the study, at the end of the three-month medication plus placebo stage, and then again at the end of the study.
At the end of the study, the researchers found that people receiving the chromium supplements gained significantly less weight than those in the placebo group (0.9 kg versus 2.2 kg, respectively). Body weight and total abdominal fat also improved in the supplemented group, compared to placebo (0.12 versus 1.17 per cent, and 12.2 sq.cm versus 32.5 sq.cm, respectively).
Cefalu said that this result is important since "chromium picolinate helped reduce abdominal fat accumulation, which is associated with a greater risk for other conditions such as abnormal lipids and hypertension."
Martin and her colleagues also report that insulin sensitivity for both fat-free mass and free-fatty acids improved for the group receiving the chromium picolinate supplements.
"This study demonstrates that chromium picolinate supplementation in subjects with type-2 diabetes who are taking sulfonylurea agents significantly improves insulin sensitivity and glucose control," wrote Martins.
"Further, chromium picolinate supplementation significantly attenuated body weight gain and visceral fat accumulation compared with the placebo group," she concluded.
Natasha Marshland, care advisor at British charity Diabetes UK told NutraIngredients.com that the trial was an interesting piece of research and that the charity would be interested to see further evidence to support the findings.
However, Marshland cautioned: "Diabetes UK doesn't advocate taking vitamins and supplements, unless clinical needs dictate it. We always advise that people should follow a healthy, balanced diet in order to get the nutrients they need."
Sales of chromium picolinate, worth around $106m (€82.4m) in 2003 in retail terms, are reported to have grown by around 25 per cent since 2002.