A low-fat diet improves peripheral insulin sensitivity in patients with Type 1 diabetes.
OBJECTIVE
To compare the effects on insulin sensitivity, body composition and glycaemic control of the recommended standard weight-maintaining diabetes diet and an isocaloric low-fat diabetes diet during two, 3-month periods in patients with Type 1 diabetes.


METHODS
Thirteen Type 1 patients were included, of whom 10 completed the cross-over study. Ten non-diabetic, matched control subjects were also examined. Body composition was estimated by dual-energy X-ray absorptiometry (DXA) whole-body scanning, diet intake was monitored by 7-day dietary record and insulin sensitivity was measured by the insulin clamp technique at baseline and after each of the diet intervention periods.


RESULTS
On an isocaloric low-fat diet, Type 1 diabetic patients significantly reduced the proportion of fat in the total daily energy intake by 12.1% (or -3.6% of total energy) as compared with a conventional diabetes diet (P = 0.039). The daily protein and carbohydrate intake increased (+4.4% of total energy intake, P = 0.0049 and +2.5%, P = 0.34, respectively), while alcohol intake decreased (-3.2% of total energy intake, P = 0.02). There was a significant improvement in insulin sensitivity on the isocaloric, low-fat diet compared with the standard diabetes diet [7.06 +/- 2.16 mg/kg/min (mean +/- sd) vs. 5.52 +/- 2.35 mg/kg/min (P = 0.03)]. However, insulin sensitivity remained 33% lower than in the control subjects (P = 0.021). No significant changes occurred in body weight or body composition. Glycated haemoglobin rose during both diet intervention periods (P = 0.18), with no difference between the two diets.


CONCLUSIONS
Change to an isocaloric, low-fat diet in Type 1 diabetic patients during a 3-month period resulted in significant improvement in insulin sensitivity without improvement in glycaemic control. However, insulin sensitivity remained 33% lower than in control subjects.
Rosenfalck
A M
AM
Department of Endocrinology, Hvidovre University Hospital, Copenhagen, Denmark. annemette@rosenfalck.com
Almdal
T
T
Viggers
L
L
Madsbad
S
S
Hilsted
J
J
D015502:Absorptiometry, Photon; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D001823:Body Composition; D016022:Case-Control Studies; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000178:diet therapy* / Q000378:metabolism; D003927:Diet, Diabetic; D018752:Diet, Fat-Restricted; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D002149:Energy Intake; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D006442:Glycated Hemoglobin