New Study Confirms Low Calorie / Long Life Link in Humans


The latest analysis of data from a large group of Japanese American men has provided the first reliable indication that a reduced-calorie diet -- between 1,700 and 2,000 calories daily -- promotes longevity in humans.

These findings confirm what has been seen in hundreds of previous animal studies but have never been replicated in a longitudinal human study, until now.

The research findings appear in an article by Dr. Bradley Willcox and colleagues at Pacific Health Research Institute and Kuakini Medical Center in Hawaii, titled "How Much Should We Eat: The Association Between Energy Intake and Mortality in a 36-Year Follow-Up Study of Japanese American Men", published in the Journal of Gerontology: Biological Sciences.

The study found that risk of death was lower in men who ate fewer calories, and was most pronounced at about 1,900 calories per day or about 15% fewer calories than the group average. This lower risk of death persisted until participants ate about 50% fewer calories than the group average.

The study utilized data from the Honolulu Heart Program, a 36-year prospective study of middle-aged men conducted at Kuakini Medical Center, and was funded by the US National Institutes of Health-Heart, Lung and Blood Institute and Aging Institute, and the American Heart Association (Hawaii).

"Dr. Willcox's work represents a significant step in confirming what many scientists had suspected--that eating fewer calories may be linked to human longevity," commented Dr. David Curb, President and CEO of PHRI, in a written statement.

Does this mean we should all start starving ourselves in order to live longer, healthier lives? "That's a popular misconception. Fewer calories does not necessarily mean eating less food", says Dr. Willcox, whose research on caloric density (CD) has been instrumental in providing a healthy solution to the obesity epidemic. "In fact," said Dr. Willcox, "Okinawan elders have been eating a restricted calorie diet for years and generally consume up to a half pound more food daily than the average American."

"The results of Dr. Willcox's fascinating study come at a time when there is much confusion among the general public regarding the optimum diet and its association with healthy aging," stated Dr. Curb.

Dr. Willcox and his team are currently studying how to help people lose weight and maintain this loss through on-line diet support programs. They hope to compare the effectiveness of low carbohydrate, low fat, and other approaches through a potential NIH-funded study.

Dr. Bradley Willcox is a nationally recognized expert on healthy aging, formerly of Harvard Medical School and currently a Clinician-Investigator at Pacific Health Research Institute. He is also Clinical Assistant Professor, University of Hawaii, where he conducts research funded by the National Institute on Aging. Dr. Willcox is Co-Principal Investigator of the Okinawa Centenarian Study and along with Doctors Craig Willcox and Makoto Suzuki, co-authored The New York Times bestseller (Clarkson-Potter/Publishers, 2001). Dr. Willcox recently published a prescriptive book on their latest research on low calorie diets and healthy weight called (Clarkson-Potter/Publishers, 2004). For more information, please visit:

Pacific Health Research Institute is a public, non-profit organization created in 1960 to conduct collaborative, multi-institutional health research designed to enhance the well being of individuals and communities in Hawaii, the Pacific, and throughout the world.