Low-carbohydrate diet in type 2 diabetes: stable improvement of bodyweight
and glycemic control during 44 months follow-up.
Jorgen V Nielsen  and Eva A Joensson
Nutrition & Metabolism 2008, 5:14doi:10.1186/1743-7075-5-14

Published:22 May 2008

Background
Low-carbohydrate diets, due to their potent antihyperglycemic effect, are an
intuitively attractive approach to the management of obese patients with
type 2 diabetes. We previously reported that a 20 % carbohydrate diet was
significantly superior to a 55-60 % carbohydrate diet with regard to
bodyweight and glycemic control in 2 groups of obese diabetes patients
observed closely over 6 months (intervention group, n = 16; controls, n=15)
and we reported maintenance of these gains after 22 months. The present
study documents the degree to which these changes were preserved in the
low-carbohydrate group after 44 months observation time, without close
follow-up. In addition, we assessed the performance of the two thirds of
control patients from the high-carbohydrate diet group that had changed to a
low-carbohydrate diet after the initial 6 month observation period. We
report cardiovascular outcome for the low-carbohydrate group as well as the
control patients who did not change to a low-carbohydrate diet.

Method
Retrospective follow-up of previously studied subjects on a low carbohydrate
diet.

Results
The mean bodyweight at the start of the initial study was 100.6+/-14.7 kg.
At six months it was 89.2+/- 14.3 kg. From 6 to 22 months, mean bodyweight
had increased by 2.7+/- 4.2 kg to an average of 92.0 +/- 14.0 kg. At 44
months average weight has increased from baseline g to 93.1+/- 14.5 kg. Of
the sixteen patients, five have retained or reduced bodyweight since the 22
month point and all but one have lower weight at 44 months than at start.
The initial mean HbA1c was 8.0 +/- 1.5 %. After 6, 12 and 22 months,HbA1c
was 6.1+/- 1.0 %, 7.0 +/- 1.3 % and 6.9 +/- 1.1 % respectively. After 44
months mean HbA1c is 6.8 +/- 1.3 %. Of the 23 patients who have used a
low-carbohydrate diet and for whom we have long-term data, two have suffered
a cardiovascular event while four of the six controls who never changed diet
have suffered several cardiovascular events.

Conclusion
Advice to obese patients with type 2 diabetes to follow a 20 % carbohydrate
diet with some caloric restriction has lasting effects on bodyweight and
glycemic control.