A Weighty Problem25. February 2013 by Joachim Goldberg
A generous waistline is my sin in life; diets are my suffering. It doesn’t seem to matter which diet I try, the kilos I fight so hard to lose always seem to creep back again. It makes no difference whether I try milkshake meals, WeightWatchers, or Atkins. The only difference is how much or how quickly the weight disappears at the outset. In every case, though, the missing kilos always wind up back where they seem to belong: on my waistline.
I wish I could share right now some marvelous new diet tip based on behavioural economics. At least by advocating it in front of the readers of this post, I would build such a strong psychological commitment that I would adhere to the endeavor. To deviate from a reference point – a norm – that I have personally and publicly erected would involve such huge psychological costs, I would have no choice. Unfortunately, I do not have any secret weight loss formula and, in any case, I wouldn’t want to turn this blog into one of those annoying online forums where some members use the details of their own weight loss programs, together with a graphic of their personal success curves, to taunt their more calorie-rich peers.
I read recently that one should not weigh oneself every day because alone the body’s water content can vary by a kilo or more in the space of 24 hours. The only important thing is the long-term result. Yet I know quite a few people who step on the scales on a daily basis (typically naked, before having breakfast, but after emptying the bladder). If there is one tip from behavioural economics for dieters it is that this ritual will not make them happy. As, for most people, losses as perceived twice as keenly as gains of the same magnitude, a 200g weight gain (a loss in this context) will bring twice as much pain as a 200g weight loss will bring pleasure. Even for those dieters who are actually succeeding in gradually losing weight, such a small variation – up or down – could easily happen from one day to the next. Especially if one wants to lose weight slowly, something that experts recommend, the dietary success can be perceived as failure if one weighs oneself too frequently.
Sheer curiosity over whether the seemingly endless self-denial is actually bearing fruit might make a surreptitious trip to the bathroom scales seem like a good idea, but it is not. The steady accumulation of those mental gains and losses will only make the task appear more painful. Give weight loss a chance: you will happier with just one trip to the scales per week.
 Consider the following weight curve: -300g (weight loss), +100g (weight gain), -100g, -200g, 0g, +200g. If measured only at the end of a week, dieters will perceive the combined weight loss of 300g. If observed on a daily basis, however, the 2:1 ratio between perceived losses and gains will result in the following series : -300g, +200g, -100g, -200g, 0g, +400g, i.e., no perception of weight loss at all.