Obesity is a huge problem in the United States and the world.  Obesity is a growing problem that is only superseded by our increasing waistlines.  Obesity, plainly, is one of the major health crises of the beginning of the 21st century.  Despite years of research and an endless list of weight loss techniques to try, obesity rates continue to grow around the world.  I have heard many times that the key to dieting is consistency.  You have to develop a plan and stick to it.  Does this mean that you must have a set plan that never deviates or can intermittent calorie restrictions be a plan?  

A study released in 2017 looked at this very topic.  The journal article, “s two days of intermittent energy restriction per week a feasible weight loss approach in obese males? A randomized pilot study”, was published in the online Nutrition & Dietetics​[1]​.  It is a pilot study, so there is expected to be further research.  This study looked to determine whether a 5:2 diet (5 days off and two days dieting) could achieve ≥5% weight loss and greater improvements in weight and biochemical markers than a standard energy-restricted diet.  The subjects were a group of 24 obese male war veterans.  The 5:2 diet included a 600

The subjects were randomized and placed on either a 5:2 diet included two days a week with a  600 calorie deficit or a standard diet with a 500 calorie deficit for the entire week.  Based on the math, you would expect the standard diet to lose more weight because 3500 calories a week is greater than 1200 in anyone’s book.  

After six months, participants in both groups experienced a significant reduction in both body weight and systolic blood pressure. Mean weight loss was 5.3 kg for the 5:2 group and 5.5 kg in the standard group.  The incredible thing is that the mean waist circumference was reduced for the 5:2 group was 8.0 cm and 6.4 cm for the standard group.   Although there was no significant difference in the amount of weight loss or WC reduction between diet groups, fat loss was higher for intermediate dieting.  The most important thing is that the standard diet was not superior, so there may be a promise to an intermittent weight loss plan.   

The bottom line: Results suggest that the 5:2 diet is a successful but not superior weight loss approach to a standard diet.  More research is needed.  The study is limited by a low number of subjects and a short time frame.  I do not think that war veterans are a group that would limit the results, but future research is needed to determine the long-term effectiveness of the 5:2 diet and its effectiveness in other population groups.