When does eating more food lower your weight? Tin and colleagues from the University of Hong Kong suggest it is when you are a child and you are skipping meals. In particular they have tested the hypothesis that skipping breakfast is associated with weight gain. They point out that the current epidemic in obesity coincides with a period of increasingly hectic lifestyles and a tendency to skip breakfast in the morning. They studied 113,457 children aged around 10 years and found 5% skipped breakfast. At baseline this group included more obese subjects and those who skipped breakfast subsequently had a greater increase in BMI over the next two years. This effect did not appear to be driven by any associations with markers of a sedentary lifestyle such as television watching.
Over the two years, as would be expected for a childhood population, all the subjects BMIs increased and the difference between groups was driven by the fact that ‘breakfast skippers’ had a greater increase. However, the absolute additional rise in BMI was strikingly small, only 0.1kg/m2. The large size of the study ensured it had enough power to identify this small effect but it is difficult to draw a useful clinical message from such a small difference. There are also problems with how you accurately characterise being a ‘breakfast skipper’. The study used self reporting and it is unclear on the accuracy of this approach especially in obese children.
One interesting conclusion that can be drawn from the study is that there is no evidence that people who skip meals, in particular breakfast, have lower weight. Therefore there seems to be no particular mandate to suggest skipping meals is in anyway effective as a weight loss strategy.