Effect of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk: A randomized 1-year trial.
BACKGROUND & AIMS
Long-term adherence to conventional weight-loss diets is limited while intermittent fasting has risen in popularity. We compared the effects of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk factors in adults with abdominal obesity and ≥1 additional component of metabolic syndrome.


METHODS & RESULTS
In total 112 participants (men [50%] and women [50%]) aged 21-70 years with BMI 30-45 kg/m2 (mean 35.2 [SD 3.7]) were randomized to intermittent or continuous energy restriction. A 6-month weight-loss phase including 10 visits with dieticians was followed by a 6-month maintenance phase without additional face-to-face counselling. The intermittent energy restriction group was advised to consume 400/600 kcal (female/male) on two non-consecutive days. Based on dietary records both groups reduced energy intake by ∼26-28%. Weight loss was similar among participants in the intermittent and continuous energy restriction groups (8.0 kg [SD 6.5] versus 9.0 kg [SD 7.1]; p = 0.6). There were favorable improvements in waist circumference, blood pressure, triglycerides and HDL-cholesterol with no difference between groups. Weight regain was minimal and similar between the intermittent and continuous energy restriction groups (1.1 kg [SD 3.8] versus 0.4 kg [SD 4.0]; p = 0.6). Intermittent restriction participants reported higher hunger scores than continuous restriction participants on a subjective numeric rating scale (4.7 [SD 2.2] vs 3.6 [SD 2.2]; p = 0.002).


CONCLUSIONS
Both intermittent and continuous energy restriction resulted in similar weight loss, maintenance and improvements in cardiovascular risk factors after one year. However, feelings of hunger may be more pronounced during intermittent energy restriction.


TRIAL REGISTRATION
www.clinicaltrials.govNCT02480504.
['Sundfør|T M|TM|', 'Svendsen|M|M|', 'Tonstad|S|S|']
D000328:Adult D000368:Aged D015415:Biomarkers D001794:Blood Pressure D031204:Caloric Restriction D008076:Cholesterol, HDL D005215:Fasting D005260:Female D006801:Humans D008297:Male D024821:Metabolic Syndrome D008875:Middle Aged D009664:Norway D056128:Obesity, Abdominal D012307:Risk Factors D013997:Time Factors D016896:Treatment Outcome D014280:Triglycerides D055105:Waist Circumference D015431:Weight Loss D055815:Young Adult
Weight loss Cardiometabolic risk factors Metabolic syndrome Intermittent energy restriction