Disclaimer, this is not a lead in to a new book, nor is it us trying to sell you the secret to weight loss but it's an interesting and developing field of work that could assist you in your weight loss endeavors, especially if you've been dieting for more than four to six weeks and you've found that you've come to a roadblock in your efforts.
The one trick to weight loss you've not tried
Ok, so this isn't actually a trick ladies and gents but just another tool to try and keep the weight loss dial moving. This method should be used baring in mind you've got everything else in control; you're aware of how much you should be eating, how much activity you should be doing, you're in a good state of health etc. etc.
There is an accumulating amount of data supporting the use of Diet Breaks to elicit better results in long term weight loss efforts. Most recently, data was achieved following the completion of the MATADOR study (Byrne et al., 2017) that showed when a group of obese men are either asked to maintain a certain caloric restriction for an extended, consistent period of time or given breaks during this prolonged time where they would consume their maintenance calories for a period of 7 to 14 days, it was those who had the "diet breaks" who ended up with the greatest fat loss.
What are diet breaks?
This is quite simply a time during a prolonged period of dieting in which the individual who is dieting eats at their approximate maintenance calories.
The thought is somewhat akin to periodisation within an exercise program, which involves a period designed to progressively overload the physiology leading to increased functional capacity followed by a period of reduced volume to mitigate overtraining and the negative effects associated with relative excessive volume. With diet breaks, the theory is that the cycling of energy restriction and maintenance allow for more successful weight loss by reducing the possible impact of adaptive thermogenesis and increasing sustainability and protocol adherence.
What is adaptive thermogenesis?
Adaptive thermogenesis, or metabolic adaptation as it may also be referred to on occasion, refers to a scaling decrease in resting energy expenditure (REE)(the calories which we would burn at complete rest) to a greater extent than that anticipated from changes in body mass and composition.
Weight loss protocols are based on our energy expenditure and prescriptions for caloric intake can be made by utilizing equations to determine energy balance based on body weight, composition and activity level. Atypically the prescriptions made by experienced diet coaches will elicit the expected results (in terms of weight loss and rate of weight loss) in the initial stages of a diet. The more prolonged a diet is and or the more severe the deficit the more likely adaptive thermogenesis will play a factor. This simply means that the weight loss we expect does not occur due to our body adapting itself to this prescribed calorie intake. This is a subject for another day but forms the basis for use of diet breaks. Of note, research has shown that between 7 - 14 days is an apparently sufficient time to normalize thermogenesis (Byrne et al., 2003, Byrne et al., 2013), with obviously longer periods between breaks or longer periods of dieting requiring larger breaks.
The research in this field stems, arguably accidentally, from a 2003 study conducted by Wing & Jeffery who implemented a design protocol to experimentally produce weight loss relapses in their subjects. They were essentially testing whether breaks during a prolonged period of dieting would effect weight loss outcomes and or induce a relapse. What they instead found was the complete opposite. Subjects who were on the break protocols actually produced similar results than those on a prolonged deficit and had improved weight loss after an 11 month follow up (although not statistically significant).
The most recent study by Byrne et al., (2017) looked to follow on this line of research. They compared two groups of obese men, one group undergoing continuous energy restriction and the other an intermittent (diet break) protocol. Byrne et al., found that diet breaks could be an effective tool for improving diet protocol results both short and longer term (notably the study was performed in obese men so may not be applicable to all populations however anecdotally i.e. first hand experience, we've found these to be successful also.), finding that fat mass loss was greater in the intermittent dieting group and REE was better preserved (after adjusting for changes in body composition). Much more research is needed, however these studies, and the accumulating data being gathered in practical application across the world, could path the way for a new, more successful modality of weight loss and weight loss maintenance.
Practical Application - What do we recommend?
First and foremost, avoid crash dieting. The greater your calorie deficit and or the greater the lack of energy availability is, the sharper the physiological response will be i.e. a more rapid and severe an effect on your hormonal levels leading to the adaptive thermogenesis we discussed.
Secondly, understand that you need to work out your correct calorie intake before decided on your food choices. This can be done on your own but the use of a nutritional coach would be a great benefit, especially for beginners or those who have struggled dieting in the past.
Thirdly, have distinct goals. Know when you are finished dieting, whether that be a number on the scale, a date in the calendar, a look you want to achieve, a dress size you'd like to get into, whatever it may be, have an end point. You can't diet forever and diet breaks, along with other tools that can be used, can only be used so much before you have to consider what the next steps are. The better your plan is the more likely it is to succeed.
Finally, apply diet breaks if you feel that you have everything else correct. If you're nutrition is correct (in terms of quantity and quality of nutritional intake), you're exercise volume is adequate, you're recovery is effective and your stress levels are relatively controlled (even then diet breaks could assist with this), then think of implementing a break.
A practical recommendation would be to take a weeks diet break every five weeks (eating at maintenance on this week), or a two week break every eight weeks (eating at maintenance).
The more lean you become and or the more prolonged the diet the more frequent the breaks may have to become. For the majority of people this protocol should work however if you're an athlete or needing to achieve a certain look it would be better to get in touch with our team to discuss how we can work together.
It's also worth noting we'll be implementing these protocols in our new program -
Byrne NM, Hills AP. (2013). Biology or behavior: which is the strongest contributor to weight gain? Current Obesity Report, 2, pp.65–76.
Byrne, N., Sainsbury, A., King, N., Hills, A. and Wood, R. (2017). Intermittent energy restriction improves weight loss efficiency in obese men: the MATADOR study. International Journal of Obesity, 42(2), pp.129-138.
Byrne, N., Weinsier, R., Hunter, G., Desmond, R., Patterson, M., Darnell, B. and Zuckerman, P. (2003). Influence of distribution of lean body mass on resting metabolic rate after weight loss and weight regain: comparison of responses in white and black women. The American Journal of Clinical Nutrition, 77(6), pp.1368-1373.
Wing, R. and Jeffery, R. (2003). Prescribed “Breaks” as a Means to Disrupt Weight Control Efforts. Obesity Research, 11(2), pp.287-291.