A randomized controlled trial of more than 100
persons with type 2 diabetes found that a low-carbohydrate, high-fat, calorie
unrestricted diet helped patients achieve better weight loss and glucose
control over a 6-month intervention compared to a high-carb, low-fat diet. The
changes were not sustained 3 months after the intervention, suggesting a need
for long-term dietary changes to maintain meaningful health benefits. The
findings are published in Annals of Internal Medicine.
More than 480 million people worldwide are
affected by type 2 diabetes. More than half of persons with diabetes also have
nonalcoholic fatty liver disease (NAFLD), which can progress to cirrhosis and
impair liver function. Prior studies suggest that weight loss improves both
diabetes control and NAFLD and restriction of carbohydrate intake improves the
control of blood sugar levels.
Researchers from the University of Southern
Denmark, Odense, Denmark, randomly assigned 165 persons with type 2 diabetes to
either a LCHF diet or a HCLF diet for 6 months. Participants in both groups
were asked to eat the same number of calories equal to their energy
expenditure. Participants on the low carb diet were asked to eat no more than
20% of their calories from carbohydrates but could have 50- 60% of their
calories from fat and 20-30% from protein. Patients on the low-fat diet were
asked to eat about half of their calories in carbohydrates and the rest evenly
split between fats and proteins. The authors found that persons on the low carb
diet reduced hemoglobin A1c by 0.59 percent more than the low-fat diet, and
also lost 3.8 kg more weight compared to those in the low-fat group. The low
carb dieters also lost more body fat and reduced their waist circumference.
Both groups had higher high-density lipoprotein cholesterol and lower
triglycerides at 6 months. However, changes were not sustained 3 months after
the intervention, suggesting that dietary changes need to be sustained over the
long term to maintain effects. The liver was not affected by the high fat
intake in the low-carb group: The researchers found no difference on the amount
of liver fat or inflammation between the two groups.
Reference:
Aleksander Krag et al, AMERICAN COLLEGE OF
PHYSICIANS, JOURNAL, Annals of Internal Medicine, DOI 10.7326/M22-1787