This is an increasingly recognized bit of bad news. Those of us who weigh more than we’d like would of course rather hear that there is some secret to fully reversing overweight and obesity. The data simply do not support that.
Instead Mann, advocates behavioural tricks and techniques to land on your “leanest liveable weight” which may well mean the fat remain fat. These behavioural tricks include putting vegetables and salads out before the meal and eating them before other foods. An interesting study cited here was an experiment on school children who were given a bunch of crudités to munch on while they wait for lunch: veggies were a bigger proportion of the meal eaten when this was done. Not rocket science, but note that we often begin our meals out with bread rather than salad. Other ideas have to do with habit disruption (e.g. avoid a route to work that goes by the bakery) and habit formation (e.g. in a restaurant you visit often always order the salad with chicken, then this soon becomes a habit that doesn’t require willpower and choice). The trickiest of these techniques is something called i-intentions. These are plans you make in advance that you can rely on to exert unconscious behavioural control. An example given is that when invited to the company Xmas party you make an i-intention to keep a glass in one hand and a napkin in the other. At the party, this just makes it harder to gobble the nibblies. The i-intention isn’t to “not have nibblies” or “only four cheese puffs”, it’s another behaviour entirely that makes freefeeding inconvenient. It was harder to easily apply i-intention formation to other circumstances, so this technique likely warrants its own book or lay article or even an online mini-course.
Behavioural conditioning is also front and centre in the discussion of exercise. After demolishing the idea that regular exercise leads to substantive weight loss in most cases, Mann makes the case that exercise is a healthy good in its own right and should be encouraged by implementing a reward system. The simplest reward is enjoyment of the activity itself, suggesting that a priority should be finding something you enjoy, rather than a certain kind of activity.
Overall, the science described in this book is well presented and interpreted. One quibble I have is the strength of wording in the section of the book concerning the relationship between overweight/obesity and longevity/health. Mann argues that the link is not nearly as clear as overwrought public health headlines suggest. There is some truth to this based on the data presented. But while it is the case that clinical indicators other than weight better predict morbidity and mortality, these clinical indicators often present in a constellation that includes overweight and obesity. This doesn’t mean that the weight itself is the health risk, but could instead be an indicator. But that does not really mean that trends in overweight and obesity are not cause for health concern beyond aesthetics. If anything the data summarized in this book are a cry for evidence-based prevention, given the inefficacy of weight loss methods. And note that the causes of increasing overweight and obesity in the population, effective methods of prevention and effective treatments may entail very different independent variables.
See you at the salad bar, before the bread arrives.