Fat men likely to live longer
according to a survey done by a research group at the Epidemiology
and Biostatistic Division at the National Cancer Centre in Tokyo.
Fat men tend to live longer than their slimmer counterparts, according to a survey done by a research group at the Epidemiology and Biostatistic Division at the National Cancer Centre in Tokyo.
Researchers investigating the connection between eating habits and life-threatening diseases chose 40,000 healthy men and women, aged from 40 to 59, from four different prefectures in Tokyo, in a study which spanned a whole decade, from 1990 to 2000.
By analysing selected results, Shoichiro Tsugane, director of the Centre, and his team found that overweight men had an advantage in terms of life expectancy.
To measure obesity, an overweight index called body-mass-index (BMI) was used in the research. BMI is calculated by dividing a person's weight by the square of his/her height. The Japan Society for the Study of Obesity recognises people with a BMI figure of more than 25 as being overweight.
The survey showed that the lowest death rate for men was for those in the BMI range of 23.0 to 24.9. The Ministry of Health and Welfare has said that a BMI of 22.0 indicates the lowest probability of people getting sick and set it as a standard level.
However, the death rate of men having a slightly higher BMI figure than the standard level is the lowest as indicated by the 10-year-long survey. In contrast, the death rate of thin men, whose BMI is from 14.0 to 18.9, is almost three times as high as the standard.
In the case of women, however, the difference in the death rate based on BMI figures was not as significant as the results for men. Tsugane commented that with the death rate for overweight and thin women almost the same, it may be necessary to rethink the notion that being fat is bad.
"It's not just Japanese either," Tsugane said. "Research conducted on Chinese and Koreans show the same results."
However, he conceded that the outcome of his research is not applicable to everyone, and that differences in age and location have a bearing.
Yuji Matsuzawa, a professor in the department of internal medicine and molecular science at Osaka University, said: "It's not always necessary to reduce your weight even if your BMI figure is over 25. With obese patients who show symptoms of diseases such as diabetes or high blood pressure, I may instruct them to to lose a little weight. But otherwise, a certain amount of fat accumulation is good for you."
Matsuzawa added that recent research has highlighted the effectiveness of fat cells. "If the amount of secretion from fat cells is proper, it helps improve the body's defense mechanisms. This is an extreme example, but if all fat cells were gone from a person, he/she would become a diabetic. Thus, having some fat is better than being skinny."
However, Dr Etsutaro Ikezono did not agree with Tsugane's findings. "Obesity causes high blood pressure and high cholesterol levels, and sooner or later it'll lead to cardiac and cerebral infraction. Weight management is necessary. Since Tsugane's research doesn't show death rate for men under 40 and over 60 years old, you can't make any definite conclusions."
