“To compare the effects of a very low carbohydrate, high unsaturated/low saturated fat diet (LC) to a high-unreﬁned carbohydrate, low-fat diet (HC) on glycemic control and CVD risk factors in T2D. “

Study Number: 34

Year: 2014

Study Design(COUNTRY 1=RCT 2= Systematic Review 3=Non-randomized controlled 4= single arm 5= post hoc analysis 6=Non-systematic review 7. Network meta-analysis 8=other 9 follow up to study): 1

Study background and AIM: "To compare the effects of a very low carbohydrate, high unsaturated/low saturated fat diet (LC) to a high-unreﬁned carbohydrate, low-fat diet (HC) on glycemic control and CVD risk factors in T2D. "

6 Months or longer: N

Number of subjects and analysis: 93

Low-carb diet arm: "Target: Carb: 14% E, <50g/day Protein: 28%E Fat: 58%E (10% saturated, 48% unsaturated) Intake: E: 1563kcal/d Carb: 56.7 g/day, 14%E Protein: 102.8 g/day, 27%E Fat: 96.5 g/day, 54%E Saturated fat: 10%E"

Comparison diet ARM(S): "High carb (HC) Target: Carb: 53% E, emphasis on low glycemic index foods Protein: 17%E Fat: 30%E (6% saturated, 24% unsaturated) Intake: E: 1587kcal/d Carb: 204.9 g/day, 50%E Protein: 73.6 g/day, 19%E Fat: 44.3 g/day, 25%E Saturated fat: 7.5%E"

Outcomes Studied: "Primary: HbA1c. Secondary: antiglycemic medication changes, lipids, SBP, and DBP and glycemic variability, as assessed by 10 outcome measures, including: area under the curve; min, max and mean glucose, intraday and interday standard deviation, mean amplitude of glycemic excursions (MAGE), continuous overall net glycemic action (CONGA-1 and 4), glucose range, mean of daily blood glucose differences (MODD)."

Result Summary: LC group achieved greater reductions in TG, medications use, and HbA1c, as well as greater increase in HDL-C.

FBG, Other Glucose Measures: "FBG BG NSS Other measures BG SS favoring LC: mean glucose, maximum glucose, glucose range, CONGA-1, CONGA-4, area under the curve, MODD. "

FBG WG Sign: *

FBG BG Sign: 0

HbA1c: At baseline, groups matched for # subjects with HbA1c ≤ 7.8. At 24 weeks, the 3 with HbA1c > 7.8 was SS higher in HC diet group, p<0.05.

HbA1c WG Sign: *

HbA1c BG Sign: 1

Total C: "WG: NR BG: N BG NSS"

Total C WG Sign: *

Total C BG: 0

HDL-C: "WG: NR BG: Y BG SS only for subjects with baseline value of <1.3 mmol/L At 24 weeks LC diet: +0.2mmol/L HC diet: +0.05 BG SS, p < 0.007"

HDL-C WG Sig: *

HDL-C BG Sig: 1

LDL-C: "WG: NR BG: N BG NSS"

LDL-C WG Sig: *

LDL-C BG Sig: 0

TG: "WG: NR BG: Y At 24 weeks LC diet: -0.5mmol/L HC diet: -0.1 BG SS p=0.001"

TG WG Sig: *

TG BG Sig: 1

TG/HDL-C ratio WG Sig: *

TG/HDL-C ratio BG Sig: *

Weight/bmi, Body Composition: "Weight and BMI WG: NR BG: N BG NSS At 24 weeks Weight LC diet: 88.0, -12.0kg HC diet: 11.5 BG NSS "

Weight/BMI WG Sig: *

Weight/BMI BG Sig: 0

SBP: "WG: NR BG: N BG NSS "

SBP WG Sig: *

SBP BG Sig: 0

DBP: "WG: NR BG: N BG NSS "

DBP WG Sig: *

DBP BG Sig: 0

Fasting Insulin: NR

Fasting Insulin WG SS: *

Fasting Insulin BG SS: *

Insulin Sensitivity/Resistance: "HOMA2-IR WG: NR BG: N BG NSS HOMA2-%B (beta cell function) WG: NR BG: N BG NSS "

Insulin Receptor Improvement WG sig: *

Insulin Receptor Improvement BG sig: 0

Inflammation: "C-reactive protein WG: NR BG: N BG NSS "

CRP WG sig: *

CRP BG sig: 0

Diabetes Medication Use: "On 3 measures WG: NR BG: Y Assessed using a medication effects score based on potency and dosage of antiglycemic meds and insulin use. Higher MES corresponds to higher antiglycemic medication usage. MES score BG SS p=0.003 Proportion that achieved meds reduction of ≥ 20%: LC diet - 67.4% HC diet - 27.7% BG SS p<0.005 Proportion that achieved meds reduction of ≥ 50%: LC diet - 34.8% HC diet - 17.0% BG SS p= 0.05 "

Safety Adverse Events: Similar small proportions experienced symptoms related to exercise program. Two in LC diet group had gastrointestinal complaints.

Retention and Compliance: "LC diet: 79% HC diet: 82% Exercise compliance similar between groups. B-hydroxybutyrate levels increased SS, threefold more on the LC compared with the HC diet after the initial 4 weeks and remained higher throughout the study, indicating adherence to diet. "

Study Author's Conclusions: "Our results suggest that a very low carbohydrate diet coupled with skills to promote behavior change may improve glycemic control in type 2 diabetes while allowing decreases in diabetes medications."

Abbreviations:

AHA - American Heart Association;

ALT - alanine aminotransferase;

AMDR - acceptable macronutrient distribution range;

AST - aspartate aminotransferase;

BG - between study groups;

BHOB - beta-hydroxybutyrate;

DBP - diastolic blood pressure;

E- energy, caloric intake;

eGFR - estimated glomerular filtration rate;

FBG - fasting blood glucose;

GGT - gamma-glutamyl transferase;

HDL-C - high-density lipoprotein cholesterol;

iGFR - isotope glomerurar filtration rate;

LDL-C - low-density lipoprotein cholesterol;

NAFLD - non-alcoholic fatty liver disease;

NR - not reported (or data needed for calculation not available);

N - no;

NA - not applicable;

NS - not specified;

NSS - not statistically significant;

SBP - systolic blood pressure;

SS - statistically significant;

TG - triglyceride;

total C - total cholesterol;

V - varied, mixed;

WG - within a study group;

WMD - weighted mean difference;

Y - yes

Number of People in Studies:

3,296 Enrolled in randomized controlled trials on 25% or less carbohydrates

2,626 Completed randomized controlled trials on 25% or less carbohydrates

79.67% 82% completion of studies

Duration of Trial

<6 Months

6-9 Months

1 -2 years

>2 years

“To compare the effects of a very low carbohydrate, high unsaturated/low saturated fat diet (LC) to a high-unreﬁned carbohydrate, low-fat diet (HC) on glycemic control and CVD risk factors in T2D. “

Abbreviations:

Number of People in Studies:

Duration of Trial

# of Trials

Join the Low-Carb Action Network to stay informed of our latest news and calls to action.

Contact

About Us