Consider the position of weight loss researchers in the early 1990s. They saw that most people who lost weight gained it back. They wanted to find out how weight loss could be maintained. How could they proceed?
One approach would be to solicit people who have lost weight and kept it off. These people would be asked to describe their lifestyles. The results of the questionnaires would be collated and examined to see if there were any similarities in the methods.
This is exactly what Doctors Rena Wing and James Hill did, starting in 1994. They established the National Weight Control Registry (NWCR). Individuals who had lost at least 30 lb., and kept it off for at least a year, were invited to sign up and fill out detailed questionnaires. This data was analyzed and the results were summarized.
Doctors Wing and Hill found that the ways NWCR participants lost weight were varied. Some joined formal programs, some did it on their own. A variety of diets were used including: restricting certain foods, counting calories or grams of fat, liquid diets, and exchange diets.
But what was remarkable was that most participants used both diet and exercise to maintain their reduced weight.
Here is a quote from a 2003 article by Doctors Wing and Hill:
We could identify few commonly shared features of how these people lost weight. The only common characteristic was that 89% of registry participants used both diet and physical activity to lose weight: only 10% used diet alone, and 1% used exercise alone. This finding is very important because most weight loss programs focus primarily on dietary restriction.
The characteristics that were common to those who successfully maintained a low weight were that they:
- adopted a low fat, high complex carbohydrate diet
- exercised regularly
- ate breakfast almost every day
- tracked their weight frequently
The first two of these ideas are the core of the SWLL.
The main finding from the NWCR was that diet alone is not sufficient for most people to achieve sustainable weight loss.
The method that works is a combination of moderate ingestion of food and drink, aerobic exercise and strength training, and building more activity into your daily life. This is the foundation for the SWLL.