Low-carbohydrate diet may help patients with diabetes achieve better weight loss and glucose control in the short term compared to a low-fat diet
Effect of low-carbohydrate, high-fat diet without calorie restriction versus high-carbohydrate, low-fat diet on type 2 diabetes and non-alcoholic fatty liver disease
Summary
Background
It is unclear whether a low-carbohydrate, high-fat (LCHF) diet is a potential treatment strategy for type 2 diabetes mellitus (T2DM), and the effect on nonalcoholic fatty liver disease (NAFLD) has not been investigated. .
Aim:
To investigate the effect of a non-calorie-restricted LCHF diet, with no intention to lose weight, on T2DM and NAFLD compared to a high-carbohydrate, low-fat (HCLF) diet.
Design:
6-month randomized controlled trial with 3-month follow-up. (ClinicalTrials.gov: NCT03068078). Odense University Hospital in Denmark from November 2016 to June 2020.
Participants:
165 participants with DM2.
Intervention:
Two diets without calorie restrictions: LCHF diet with 50 to 60 percent energy (E%) fat, less than 20E% carbohydrates, and 25E% to 30E% protein and HCLF diet with 50E% to 60E% carbohydrates, 20E% to 30E% fats, and 20E% to 25E% proteins.
Measurements:
Glycemic control, serum lipid levels, metabolic markers and liver biopsies to evaluate NAFLD.
Results:
The mean age was 56 years (SD, 10) and 58% were women. Compared with the HCLF diet, participants on the LCHF diet had greater improvements in hemoglobin A1c (mean difference in change, −6.1 mmol/mol [95% CI, −9.2 to −3.0 mmol /mol] or −0.59% [CI, − 0.87% to -0.30%]) and lost more weight (mean difference in change, -3.8 kg [CI, -6.2 to - 1.4kg]).
Both groups had higher high-density lipoprotein cholesterol and lower triglycerides at 6 months.
Changes in low-density lipoprotein cholesterol were less favorable in the LCHF diet group than in the HCLF diet group (mean difference in change, 0.37 mmol/L [CI, 0.17 to 0.58 mmol /L] or 14.3 mg/dL [CI, 6.6 to 22.4 mg/dL]).
No statistically significant changes were detected between groups in NAFLD assessment. The changes were not maintained at the 9-month follow-up.
Limitation:
Open trial, self-reported compliance, unintended weight loss, and lack of adjustment for multiple comparisons.
Conclusion: People with T2DM who followed an LCHF diet without caloric restrictions for 6 months had greater clinically significant improvements in glycemic control and weight compared to those who followed an HCLF diet, but the changes were not maintained 3 months after the intervention. |
Comments
A randomized controlled trial of more than 100 people with type 2 diabetes found that a low-carbohydrate, high-fat diet with no caloric restrictions helped patients achieve better weight loss and glucose control during a 6-month intervention compared to a high carbohydrate, low calorie diet. -diet rich in fat. The changes were not maintained 3 months after the intervention, suggesting the need for long-term dietary changes to maintain significant health benefits. The findings are published in Annals of Internal Medicine.
More than 480 million people worldwide have type 2 diabetes. More than half of people with diabetes also have nonalcoholic fatty liver disease (NAFLD), which can progress to cirrhosis and affect liver function. Previous studies suggest that weight loss improves both diabetes and NAFLD control and restricting carbohydrate intake improves control of blood sugar levels.
Researchers at the University of Southern Denmark, Odense, Denmark, randomly assigned 165 people with type 2 diabetes to an LCHF or HCLF diet for 6 months. Participants in both groups were asked to eat the same amount 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 get 50 to 60% of their calories from fat and 20 to 30% from protein. . Patients on the low-fat diet were asked to eat about half their calories in carbohydrates and the rest divided evenly between fat and protein. The authors found that people on the low-carb diet reduced hemoglobin A1c by 0.59 percent more than those on the low-fat diet, and also lost 3.8 kg more weight compared to those in the low-fat group. .
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, the changes were not maintained 3 months after the intervention, suggesting that dietary changes must be maintained long-term to maintain the effects.
The liver was not affected by high fat consumption in the low-carb group: the researchers found no difference in the amount of liver fat or inflammation between the two groups.
