According to the team, weight losses achieved by 1 year of exercise with no change in food intake or 1 year of calorie restriction resulted in significant and similar improvements in glucose tolerance and insulin action.

Weight losses achieved with either approach normalized body weight in 52 percent of the overweight men and women in the study.

"On average, participants in our study performed 60 minutes of cardiovascular exercise, such as brisk walking, almost every day of the week and this resulted in weight loss of approximately 16 pounds in 1 year," Weiss told Reuters Health. "Some participants performed substantially more exercise (up to 90 min/d) and had much greater weight loss (30-40 lbs)."

A caveat, Weiss said, "is that food intake must not increase when a person starts an exercise program to lose weight. Many people think that is okay to eat more food if they exercise or that they need to drink sports drinks or eat energy bars if they exercise. However, a modest increase in food intake can quickly offset the calorie-burning benefit of substantial amounts of exercise," he warned.

The findings from this study, Weiss emphasized, should not be taken to indicate that all aspects of health benefit equally from caloric restriction and exercise-induced weight loss. "For example, we recently published a paper showing that exercise provided greater benefits than caloric restriction with respect to muscle strength and cardiovascular fitness and will soon publish additional papers showing that other areas of health may benefit more from one intervention or the other."

SOURCE: American Journal of Clinical Nutrition, December 2006.

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Japan scientists find gene linked to heavy smoking

Last Updated: 2006-12-06 10:24:25 -0400 (Reuters Health)

TOKYO - A team of Japanese scientists have found a gene closely linked to nicotine addiction, which could lead to more effective ways for smokers to kick the habit, a Japanese daily said on Wednesday.

The team at Osaka University found that among heavy smokers -- defined as those who light up as soon as they get up in the morning -- a gene responsible for producing an enzyme that breaks down nicotine is more active than others, the Nihon Keizai Shimbun reported.

After examining the gene CYP2A6 among 300 smokers and those who had smoked in the past, the scientists found that 70 percent of those with a highly active type of the gene were highly addicted to nicotine.

The percentage of heavy smokers among those with a less active CYP2A6 was lower at 40 percent, the finding showed.

If doctors can find out the type of the gene in patients who want to quit smoking, they can change treatment methods accordingly, such as adjusting the amount of nicotine patches prescribed to the smoker, the paper said.

Copyright © 2006 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.