On any given day, at least one out of every four North Americans is on a diet. In North American, we spend more than $30 billion annually on various weight-loss methods, most of which fail. Excess body weight is associated with numerous health-related problems including increased risk for coronary artery disease, diabetes, and high cholesterol. Osteoarthritis of the knee is also more common in those who are overweight. Unfortunately, 95 percent of people who lose weight are unsuccessful at keeping the weight off. Moreover, an obsession with weight and weight loss can lead to practices of self-imposed starvation (anorexia nervosa), which is a serious medical and mental health condition. Have you ever wondered how some people who lose large amounts of weight mange to keep it off over the long term, while others regain it easily? So have Dr. James O. Hill, PhD and Dr. Rena Wing, PhD, researchers from University of Colorado and Brown University, who established the National Weight Control Registry (NWCR) in 1994. The objective of the NWCR is to study the behaviour and psychology of individuals who are weight maintainers – that is, those who have lost weight and kept it off. By attaining insight into how they do it, those who struggle with weight management can adopt strategies that are known to set most people up for success. These are the finding thus far from the Registry:
- 80 percent of the participants are women, and 20 percent are men.
- The average woman is 45 and currently weighs 145 lbs, and the average man is 49 and currently weighs 190 lbs.
- Registry members have lost an average of 66 lbs and kept if off for 5.5 years. However, weight losses have ranged from 30 to 300 lbs, and duration of successful weight loss has ranged from 1 to 66 years!
- Forty-five percent of participants have lost the weight independently, while the other 55 percent have used a program.
- Ninety-eight percent of participants modified their food intake in some way to lose weight, primarily to a low-fat, lower-calorie diet.
- Ninety-four percent increased their physical activity, with walking the most common form of activity reported.
- Most eat breakfast every day.
- Most weigh themselves at least once a week.
- Sixty-two percent watch less than ten hours of tv per week.
- Ninety percent exercise, on average, about one hour each day.
The Bottom Line: Successful weight loss must involve a combination of dietary modification and regular exercise. Exercise volume must be sufficiently high – what we have learned from the NWCR is that an hour a day of moderate- or high-intensity exercise is ideal. In addition, self-monitoring is crucial to long-term success. Lastly, eat breakfast and don’t watch too much tv! A recent study found that people who lose weight and keep it off have fewer household televisions. References:
- American Council on Exercise (2003). Personal Trainer Manual. San Diego: American Council on Exercise.
- National Weight Control Registry website, www.nwcr.ws
- Gorin, A. et al. (2010). Decreasing household television time: A pilot study of combined behavioural and environmental intervention. Behavioral Interventions, 21(4), pp. 273-280.