Weight-loss programs focussed on positive behavioural changes typically include self-monitoring of diet, physical activity and body weight as a cornerstone component. The effectiveness of self-monitoring in these programs has undergone close scientific scrutiny.
Many programs that aim to promote weight loss through gradual lifestyle changes incorporate behaviour-change strategies such as self-monitoring as a key element. Self-monitoring is where the person makes a record of their dietary intake and physical activity to help increase awareness of their current behaviours.
There is a strong theoretical foundation for self-monitoring as it is closely linked to behaviour change. The process of changing dietary and exercise habits requires well-developed self-control skills. An honest and consistent appraisal of a person’s current behaviours is needed to help effect long-term positive habit changes.
With self-monitoring featuring so prominently in weight-loss programs focussed on behavioural change, it is surprising that the evidence for its benefit has not been systematically evaluated through the scientific literature. A recent review  of self-monitoring of diet, physical activity, and body weight in behavioural weight-loss studies has now filled this gap.
What the review found
Of the 22 studies evaluated, a variety of different methods were used to perform self-monitoring. A paper diary was the most common approach, but the Internet, personal digital assistants, and digital scales also featured in the studies. Despite the different designs of the weight-loss programs, the researchers could identify a clear positive association between the degree of adherence to self-monitoring and weight loss success.
The major limitations of the reviewed studies were the many issues with the study designs used, and the predominant use of white females as the study group making inferences about how self-monitoring may work for males or other racial groups difficult.
To weigh or not to weigh?
Compared to recording food intake and physical activity levels, self-monitoring of body weight is a more recent recommendation in weight-loss programs. On the surface, recommending people to weigh themselves daily seems counter-intuitive as it may create an unhealthy fixation with body weight and body image. Frequent self-weighing however is associated with weight loss and a lower risk of weight regain. It is likely that the regular feedback given by the scales is needed to help keep weight in check by preventing the gradual weight gain over time that most people experience
What it all means
Whether it is a paper diary, mobile phone app, or Internet site, keeping a log of food eaten, steps walked, and weight lost or gained will help tip the balance in making lifestyle habit changes that are effective for successful weight management.
Confused about the mixed soup of nutrition messages being stirred through the media? Tim maintains an active nutrition blog at www.thinkingnutrition.com.au  where you'll find the latest nutrition research and controversies discussed in straight forward language, distilling out what you need to know for your better health.