How frequently you can cheat on your diet really depends on what the diet is and what you mean by ‘cheating’. In theory, the odd dietary lapse should not totally derail weight loss, and you can still have an energy (calorie) deficit overall, despite eating normally or even overeating on occasions.
Indeed, we know that people ordinarily do not marry calorie intake to energy requirements on a meal by meal, or even day to day, basis, but rather you need to look at the balance between intake and expenditure over several days perhaps several weeks to see the true picture.
Tear Up The Rule Book
Most diets designed for weight loss are often based around rules to follow (e.g., restricting certain foods or food groups), or following a strict regime or meal pattern. They are also, by their nature, finite, such that they are really a means to an end, rather than a continuous lifelong change.
Even if the expectation is that you adopt lifelong behaviour change, we know observationally that individuals rarely continue the diet much beyond the ‘active’ weight loss stage. The very notion of ‘cheating’ on a diet underpins much of what is wrong with many diets, as they rely on consistent obedience to the rules, or some continual abstention, which creates an ‘all or nothing’ perception.
When on the diet, all is good, but once you fall off the diet, this can often lead to exaggerated disobedience and compensatory eating, of the mind of “well I may as well eat X, Y Z now”, and go back to the diet tomorrow, or another day.
An alternative approach would be to follow a diet that purposefully allows for flexibility or deliberately accounts for cheat days or periods within the rules of the diet. These diets are attractive in that they allow some free eating or having treat foods/meals, and can also be socially more acceptable, allowing people to socialise and entertain while still on the diet.
An extreme example of this type of diet is intermittent fasting, popularised into regimes such as the 5:2 diet or the 16:8 (time-restricted feeding). Traditional intermittent fasting diets of alternate fasting and feeding days allows free eating on non-diet days, yet overall, people still eat less across the week, partly because people cannot easily compensate for the large energy deficit (often upwards of 2000kcal) on the fast days, by overeating on the non-fast days. Moreover, observationally people following intermittent fasting diets often end up eating less than they would normally have done even on the non-restricted days.
But going back to the nature of most ‘diets’. By following the rules, or embarking on a new regime, people become conscious of what they are eating and are more mindful of certain behaviours, which can help build self-efficacy when it comes to diet as a by-product if recognised and managed properly.
So, to answer the question, deliberately allowing cheating is probably a good strategy when it comes to “dieting”, as that flexibility can lead to a better overall management of intake, and a greater likelihood of sustaining any long-term benefits beyond just weight loss.
If you want to find out more about sustainable weight loss, sign up for our 7-day course on the topic here.
Written by psychologist and behaviour change expert, Dr. Aria Campbell-Danesh, DClinPsy, the course will guide you through a number of practical steps, including creating an actionable plan, to help you maintain the positive behaviour patterns that will make a lasting impact on your health and wellbeing.