title: Carbohydrate restriction has a more favorable impact on the metabolic syndrome than a low fat diet.
abstract: We recently proposed that the biological markers improved by carbohydrate restriction were precisely those that define the metabolic syndrome (MetS), and that the common thread was regulation of insulin as a control element. We specifically tested the idea with a 12-week study comparing two hypocaloric diets (approximately 1,500 kcal): a carbohydrate-restricted diet (CRD) (%carbohydrate:fat:protein = 12:59:28) and a low-fat diet (LFD) (56:24:20) in 40 subjects with atherogenic dyslipidemia. Both interventions led to improvements in several metabolic markers, but subjects following the CRD had consistently reduced glucose (-12%) and insulin (-50%) concentrations, insulin sensitivity (-55%), weight loss (-10%), decreased adiposity (-14%), and more favorable triacylglycerol (TAG) (-51%), HDL-C (13%) and total cholesterol/HDL-C ratio (-14%) responses. In addition to these markers for MetS, the CRD subjects showed more favorable responses to alternative indicators of cardiovascular risk: postprandial lipemia (-47%), the Apo B/Apo A-1 ratio (-16%), and LDL particle distribution. Despite a threefold higher intake of dietary saturated fat during the CRD, saturated fatty acids in TAG and cholesteryl ester were significantly decreased, as was palmitoleic acid (16:1n-7), an endogenous marker of lipogenesis, compared to subjects consuming the LFD. Serum retinol binding protein 4 has been linked to insulin-resistant states, and only the CRD decreased this marker (-20%). The findings provide support for unifying the disparate markers of MetS and for the proposed intimate connection with dietary carbohydrate. The results support the use of dietary carbohydrate restriction as an effective approach to improve features of MetS and cardiovascular risk.
authors.affiliation: Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Storrs, CT 06269-1110, USA. jeff.volek@uconn.edu
authors.forename: Jeff S
authors.initials: JS
authors.lastname: Volek
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Phinney
authors.forename: Cassandra E
authors.initials: CE
authors.lastname: Forsythe
authors.forename: Erin E
authors.initials: EE
authors.lastname: Quann
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Wood
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Puglisi
authors.forename: William J
authors.initials: WJ
authors.lastname: Kraemer
authors.forename: Doug M
authors.initials: DM
authors.lastname: Bibus
authors.forename: Maria Luz
authors.initials: ML
authors.lastname: Fernandez
authors.forename: Richard D
authors.initials: RD
authors.lastname: Feinman
mesh_terms: D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D001823:Body Composition; D015992:Body Mass Index; D031204:Caloric Restriction; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004041:Dietary Fats / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome / Q000517:prevention & control*; D008875:Middle Aged
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D007328:Insulin