A Very Low-Carbohydrate, Low–Saturated Fat Diet for Type 2 Diabetes Management: A Randomized Trial

Abstract

OBJECTIVETo comprehensively compare the effects of a very low-carbohydrate, highunsaturated/low-saturated fat diet (LC) with those of a high-unrefined carbohydrate, low-fat diet (HC) on glycemic control and cardiovascular disease (CVD) risk factors in type 2 diabetes (T2DM). RESEARCH DESIGN AND METHODSObese adults (n = 115, BMI 34.4 6 4.2 kg/m 2 , age 58 6 7 years) with T2DM were randomized to a hypocaloric LC diet (14% carbohydrate [<50 g/day], 28% protein, and 58% fat [<10% saturated fat]) or an energy-matched HC diet (53% carbohydrate, 17% protein, and 30% fat [<10% saturated fat]) combined with structured exercise for 24 weeks. The outcomes measured were as follows: glycosylated hemoglobin (HbA 1c ), glycemic variability (GV; assessed by 48-h continuous glucose monitoring), antiglycemic medication changes (antiglycemic medication effects score [MES]), and blood lipids and pressure. RESULTSA total of 93 participants completed 24 weeks. Both groups achieved similar completion rates (LC 79%, HC 82%) and weight loss (LC 212.0 6 6.3 kg, HC 211.5 6 5.5 kg); P ‡ 0.50. Blood pressure (29.8/27.3 6 11.6/6.8 mmHg), fasting blood glucose (21.4 6 2.3 mmol/L), and LDL cholesterol (20.3 6 0.6 mmol/L) decreased, with no diet effect (P ‡ 0.10). LC achieved greater reductions in triglycerides (20.5 6 0.5 vs. 20.1 6 0.5 mmol/L), MES (20.5 6 0.5 vs. 20.2 6 0.5), and GV indices; P £ 0.03. LC induced greater HbA 1c reductions (22.6 6 1.0% [228.4 6 10.9 mmol/mol] vs. 21.9 6 1.2% [220.8 6 13.1 mmol/mol]; P = 0.002) and HDL cholesterol (HDL-C) increases (0.2 6 0.3 vs. 0.05 6 0.2 mmol/L; P = 0.007) in participants with the respective baseline values HbA 1c >7.8% (62 mmol/mol) and HDL-C <1.29 mmol/L. CONCLUSIONSBoth diets achieved substantial improvements for several clinical glycemic control and CVD risk markers. These improvements and reductions in GV and antiglycemic medication requirements were greatest with the LC compared with HC. This suggests an LC diet with low saturated fat may be an effective dietary approach for T2DM management if effects are sustained beyond 24 weeks.

Macronutrient Composition and Management of Non-Insulin-Dependent Diabetes Mellitus (NIDDM): A New Paradigm for Individualized Nutritional Therapy in Diabetes Patients

“…However, a common message is that high carbohydrate intake (>50%) does not favorably affect TG and HDL in patients with diabetes. A benefit of low-carb versus low-fat diets has also been reported in other studies regarding HDL levels [40,43,48,56], TC/HDL ratio [27,56], and triglycerides [27,43,48,56].…”

“…Consistently with the aforementioned results, most RCTs in patients with diabetes have reported that a greater reduction in HbA1c levels is achieved after carbohydrate restriction rather than after protein or lipid restriction. Specifically, significant reductions in HbA1c have been detected at 3 and 6 months using very low-carb or low-carb diets versus lowfat diets [47][48][49], even when there was no upper limit for SFA intake [44]. Similarly, Elhanyay et al found that a low-carb MD produced a greater improvement in HbA1c than a traditional MD or a low-fat diet at 1 year [43], whereas studies comparing diets with ≥40% carb percentage, differing mainly in protein and lipid content, have reported similar reduction rates of HbA1c at 1 year [42,45,50].…”

Obvious impairment of attention and processing speed in patients with schizoaffective disorder

“…Take meal plan, for example. How meal composition affects glycaemia, satiety and weight management is well documented in the literature [2][3][4][5][6][7][8][9][10][11][12][13][14] and in the official guidelines from diabetes organizations [15]. Balancing the meals by adding lean protein, extra fiber, healthy fat and vegetables has consistently shown glycaemia benefits.…”

Importance of low carbohydrate diets in diabetes management

“…43 Recently, Tay et al reported on a randomized controlled study investigating hypocaloric low carbohydrate versus high carbohydrate diets over 24 weeks and 1 year, respectively, in obese adults with T2DM. 44,45 Saturated fat intake was limited to ,10% despite total fat intake being 58% and carbohydrate 14% of the total energy intake in the low carbohydrate group. Intensive dietary counseling and a physical activity plan were included.…”

“…36 Of concern are recent data suggesting that increasing LDL cholesterol in the Atkins diet may have detrimental effects on vascular function. 44 Additionally, it is questionable whether the increase in HDL provides any meaningful benefit, further compounding the adverse effect of a VLCD in obesity and T2DM. However, these adverse effects may be overcome.…”