title: Effect of a low-carbohydrate, ketogenic diet program compared to a low-fat diet on fasting lipoprotein subclasses.
abstract: BACKGROUND
  Low-carbohydrate, ketogenic diets (LCKD) are effective for weight loss, but concerns remain regarding cardiovascular risk. The purpose of this study was to determine the effect of an LCKD program on serum lipoprotein subclasses.
  
  
  METHODS
  This was a randomized, two-arm clinical trial in an outpatient research clinic involving overweight, hyperlipidemic community volunteers motivated to lose weight. Subjects were randomized to either an LCKD (n = 59) and nutritional supplementation (including fish, borage and flaxseed oil), or a low-fat, reduced-calorie diet (LFD, n = 60). The main outcomes were fasting serum lipoprotein subclasses determined by nuclear magnetic resonance analysis.
  
  
  RESULTS
  The mean age of subjects was 44.9 years, the mean BMI was 34.4 kg/m(2), and 76% were women. Comparing baseline to 6 months, the LCKD group had significant changes in large VLDL (-78%), medium VLDL (-60%), small VLDL (-57%), LDL particle size (+2%), large LDL (+54%), medium LDL (-42%), small LDL (-78%), HDL particle size (+5%), large HDL (+21%), and LDL particle concentration (-11%). Compared with the LFD group, the LCKD group had greater reductions in medium VLDL (p = 0.01), small VLDL (p = 0.01) and medium LDL (p = 0.02), and greater increases in VLDL particle size (p = 0.01), large LDL (p = 0.004), and HDL particle size (p = 0.05).
  
  
  CONCLUSIONS
  The LCKD with nutritional supplementation led to beneficial changes in serum lipid subclasses during weight loss. While the LCKD did not lower total LDL cholesterol, it did result in a shift from small, dense LDL to large, buoyant LDL, which could lower cardiovascular disease risk.
authors.affiliation: Department of Medicine, Duke University Medical Center, Durham, NC 27705, USA. ewestman@duke.edu
authors.forename: Eric C
authors.initials: EC
authors.lastname: Westman
authors.forename: William S
authors.initials: WS
authors.lastname: Yancy
authors.forename: Maren K
authors.initials: MK
authors.lastname: Olsen
authors.forename: Tara
authors.initials: T
authors.lastname: Dudley
authors.forename: John R
authors.initials: JR
authors.lastname: Guyton
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000554:Ambulatory Care Facilities; D044383:Black People / Q000706:statistics & numerical data; D015992:Body Mass Index; D008076:Cholesterol, HDL / Q000097:blood; D018752:Diet, Fat-Restricted; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004041:Dietary Fats / Q000008:administration & dosage*; D005215:Fasting; D005260:Female; D006801:Humans; D008074:Lipoproteins / Q000097:blood* / Q000145:classification; D008297:Male; D008875:Middle Aged; D019906:Nuclear Magnetic Resonance, Biomolecular; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology; D044465:White People / Q000706:statistics & numerical data
chemical_list: D008076:Cholesterol, HDL; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D008074:Lipoproteins