Scientists at the Fred Hutchinson Cancer Research Center in Seattle, in a study that looked at the impact of various self-monitoring techniques in older overweight and obese women, showed that simple changes in behavior can make a difference on the scales.

They found that in the year-long study women who kept journals lost six pounds (2.7 kgs) more than those you didn't, but if they skipped meals they dropped eight pounds (3.6 kgs) less than women who ate regularly.

Ladies who lunched in a restaurant at least weekly lost on average five fewer pounds (2.3 kgs).

"Knowing what you are eating and knowing how much you are eating seem to be the key," Anne McTiernan, the director of the Hutchinson Center's Prevention Center who conducted the study, said in an interview.

"For individuals who are trying to lose weight, the No. 1 piece of advice based on these study results would be to keep a food journal to help meet daily calorie goals."

McTiernan said the more journals the women completed, the more weight they lost. Recording what they ate increased the women's awareness of the foods and calories they consumed.

DIET AND EXERCISE

Expanding waistlines are a growing problem around the globe, leading to increased health problems and costs. Figures from the Paris-based Organization for Economic Co-operation and Development (OECD) showed obesity rates ranged from a low of 4 percent in Japan and Korea to 30 percent or more in the United States and Mexico.

Body mass index (BMI), which is a measurement that compares weight and height are used to measure obesity. A BMI of 30 or more is considered obese, while a BMI of 25 to 29 is considered overweight.

McTiernan and her team studied 123 women, aged 50 to 75 years old, who lived in the Seattle area in the dietary weight loss intervention study. Their findings are published in the Journal of the Academy of Nutrition and Dietetics.

They divided the women into two groups, diet only and exercise plus diet, and assessed their food intake, weight-control strategies, meal patterns and encouraged them to eat between 1200 and 2,000 calories a day.

At the end of the study women in both groups lost an average of 10 percent of their body weight.

"Exercise alone does not cause very much weight loss. Most studies have shown that with exercise alone you might be able to lose about two to three pounds over a year," McTiernan explained.

"What exercise does do is keep weight off-long term and it helps prevents loss of muscle."

The researchers advised people trying to lose weight to record everything they eat, to be accurate, to measure portions and to read labels. Accuracy was also important, so any toppings or condiments added to food should also be included in the journal.

"It was the first study to look at a range of eating and weight-loss behaviors to see which ones worked and which ones didn't," said McTiernan. "These are the ones that made the difference."

(Reporting by Patricia Reaney; editing by Christine Kearney and Sofina Mirza-Reid)

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