Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet.
BACKGROUND
Trials comparing the effectiveness and safety of weight-loss diets are frequently limited by short follow-up times and high dropout rates.


METHODS
In this 2-year trial, we randomly assigned 322 moderately obese subjects (mean age, 52 years; mean body-mass index [the weight in kilograms divided by the square of the height in meters], 31; male sex, 86%) to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, non-restricted-calorie.


RESULTS
The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (P<0.05 for all comparisons among treatment groups). The low-carbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (P<0.05 for all comparisons among treatment groups). The mean weight loss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (P<0.001 for the interaction between diet group and time); among the 272 participants who completed the intervention, the mean weight losses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (P<0.001 for the interaction among diabetes and Mediterranean diet and time with respect to fasting glucose levels).


CONCLUSIONS
Mediterranean and low-carbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions. (ClinicalTrials.gov number, NCT00160108.)
Shai
Iris
I
S. Daniel Abraham Center for Health and Nutrition, Ben-Gurion University of the Negev, Beer-Sheva, Israel. irish@bgu.ac.il
Schwarzfuchs
Dan
D
Henkin
Yaakov
Y
Shahar
Danit R
DR
Witkow
Shula
S
Greenberg
Ilana
I
Golan
Rachel
R
Fraser
Drora
D
Bolotin
Arkady
A
Vardi
Hilel
H
Tangi-Rozental
Osnat
O
Zuk-Ramot
Rachel
R
Sarusi
Benjamin
B
Brickner
Dov
D
Schwartz
Ziva
Z
Sheiner
Einat
E
Marko
Rachel
R
Katorza
Esther
E
Thiery
Joachim
J
Fiedler
Georg Martin
GM
Blüher
Matthias
M
Stumvoll
Michael
M
Stampfer
Meir J
MJ
D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D050528:Diet, Carbohydrate-Restricted; D018752:Diet, Fat-Restricted; D038441:Diet, Mediterranean; D002149:Energy Intake; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007659:Ketones / Q000652:urine; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000178:diet therapy* / Q000652:urine; D011795:Surveys and Questionnaires; D015431:Weight Loss
D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007659:Ketones; D008055:Lipids