A randomized trial of a low-carbohydrate diet vs orlistat plus a low-fat diet for weight loss.
BACKGROUND
Two potent weight loss therapies, a low-carbohydrate, ketogenic diet (LCKD) and orlistat therapy combined with a low-fat diet (O + LFD), are available to the public but, to our knowledge, have never been compared.


METHODS
Overweight or obese outpatients (n = 146) from the Department of Veterans Affairs primary care clinics in Durham, North Carolina, were randomized to either LCKD instruction (initially, <20 g of carbohydrate daily) or orlistat therapy, 120 mg orally 3 times daily, plus low-fat diet instruction (<30% energy from fat, 500-1000 kcal/d deficit) delivered at group meetings over 48 weeks. Main outcome measures were body weight, blood pressure, fasting serum lipid, and glycemic parameters.


RESULTS
The mean age was 52 years and mean body mass index was 39.3 (calculated as weight in kilograms divided by height in meters squared); 72% were men, 55% were black, and 32% had type 2 diabetes mellitus. Of the study participants, 57 of the LCKD group (79%) and 65 of the O + LFD group (88%) completed measurements at 48 weeks. Weight loss was similar for the LCKD (expected mean change, -9.5%) and the O + LFD (-8.5%) (P = .60 for comparison) groups. The LCKD had a more beneficial impact than O + LFD on systolic (-5.9 vs 1.5 mm Hg) and diastolic (-4.5 vs 0.4 mm Hg) blood pressures (P < .001 for both comparisons). High-density lipoprotein cholesterol and triglyceride levels improved similarly within both groups. Low-density lipoprotein cholesterol levels improved within the O + LFD group only, whereas glucose, insulin, and hemoglobin A(1c) levels improved within the LCKD group only; comparisons between groups, however, were not statistically significant.


CONCLUSIONS
In a sample of medical outpatients, an LCKD led to similar improvements as O + LFD for weight, serum lipid, and glycemic parameters and was more effective for lowering blood pressure.


BACKGROUND
clinicaltrials.gov Identifier: NCT00108524.
Yancy
William S
WS
Center for Health Services Research in Primary Care, Department of Veterans Affairs Medical Center, Durham, North Carolina, USA. yancy006@mc.duke.edu
Westman
Eric C
EC
McDuffie
Jennifer R
JR
Grambow
Steven C
SC
Jeffreys
Amy S
AS
Bolton
Jamiyla
J
Chalecki
Allison
A
Oddone
Eugene Z
EZ
D000328:Adult; D019440:Anti-Obesity Agents / Q000627:therapeutic use*; D050528:Diet, Carbohydrate-Restricted; D018752:Diet, Fat-Restricted; D005260:Female; D006801:Humans; D007783:Lactones / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy*; D000077403:Orlistat; D015431:Weight Loss
D019440:Anti-Obesity Agents; D007783:Lactones; D000077403:Orlistat