No connection between dieting and improvements in health
In a separate study published last December, Tomiyama, former UCLA psychology faculty member Traci Mann (now at the University of MinnesotaMinneapolis) and UCLA graduate student Britt Ahlstrom analyzed 21 long-term studies on weight loss and health and found no clear relationship between weight loss and health improvements related to hypertension, diabetes, cholesterol and blood glucose.
"We found no connection whatsoever between the amount of weight loss whether small or large and any of these health outcomes," said Tomiyama of the study, which appeared in the health section of the journal, Social and Personality Psychology Compass.
"Everyone assumes that the more weight you lose, the healthier you are, but the lowest rates of mortality are actually in people who are overweight," she said. "At a body mass index of 30, which is labeled obese, there is no increased risk of mortality. This has now been shown over and over again. The highest rate of mortality is in the underweight people."
The research findings also confirmed the results of a 2007 study in which Tomiyama, Mann and colleagues analyzed 31 long-term studies and found that people can initially lose 5 to 10 percent of their weight on any number of diets, but the majority regain all the weight, plus more. Only a small minority, they discovered, sustain their weight loss.
"Eating in moderation is a good idea for everybody, and so is regular exercise," Mann said at the time of the initial study.
"If dieting worked, it wouldn't be a $60 billion dollar industry," said Tomiyama, who noted that trying to be thin is similar to trying to be taller.
"The genetic power over weight is about the same as the power of genes over your height," she said. "People who say it's yo
|Contact: Stuart Wolpert|
University of California - Los Angeles