Tallying the number of carbohydrates in the diet may be helpful to people using an insulin pump to treat type 1 diabetes, a study suggests.
The study, of 61 adults on continuous subcutaneous insulin therapy, found that those who learned to count carbs had a small reduction in weight and waist size after six months.
They also reported gains in quality of life and at least for those who consistently counted their carbs with each meal an improvement in glycaemic control.
The findings, published online in Diabetes Care, do not prove that carb counting is the answer for people with type 1 diabetes.
But it's widely recommended that people on insulin try to estimate the carbohydrate content of their meals to help calculate their insulin doses, said Dr Sanjeev Mehta, of the Joslin Diabetes Centre and Harvard Medical School in Boston.
"There is no definitive data to suggest the superiority of one method over another in terms of ease of use or (blood sugar) control," Dr Mehta, who was not involved in the study, said.
Until now, no studies had looked at whether carb counting is specifically useful to people on insulin pump therapy.
For the new study, researchers led by Dr Andrea Laurenzi, of San Raffaele Vita-Salute University in Milan, recruited 61 adults on insulin pump therapy. They randomly assigned them to either learn how to count carbohydrates or serve as part of a control group.
In sessions with a dietitian, participants in the carb-counting group learned how to calculate the amount of carbohydrates in each of their meals and estimate how much insulin they would need to "cover" those carbs.
After six months, Dr Laurenzi's team found, the carb-counters showed a slight reduction in weight and waist circumference, on average possibly, the researchers say, because they were paying closer attention to their diets or exercise habits.
When the researchers looked at the whole carb-counting group, there was no clear effect on haemoglobin A1C levels. But when they focused just on the 20 participants who consistently counted carbs for most of their meals, there was evidence of better blood sugar control.
Dr Mehta, however, said that finding is of "uncertain significance".
And in general, he said, the study had too many limitations to draw firm conclusions. One problem, he noted, is that it's unclear what kind of intervention the control group had – whether they paid no attention to their carbs, or used another method to estimate them.
(Reuters Health, Amy Norton, March 2011)