By Danielle Demetriou in Tokyo
Contrary to the widely held belief that it is healthier to be slim, researchers in Japan found that the life expectancy of the overweight at 40 was six years longer than that of their thinner counterparts.
Those who were slimmer were also at higher risk of cardiovascular disease, according to the major study, conducted over a ten-year period by scientists at Tohoku University.
Researchers examined the health, weight and life expectancy of 44,000 people aged between 40 and 79 living in the Miyagi Prefecture region of Japan, Kyodo News reported.
People were divided into four categories based on their body mass index (BMI) – including underweight, normal, overweight and obese – before scientists calculated their life expectancy.
The study found that among those aged 40, the overweight category topped the polls in terms of the longest life expectancy, with expectations of an average of 40.5 extra years for men and 47 years for women.
Those classed as “normal” weight followed closely behind, with 38.7 additional years expected among men and 46.3 among women, the study showed.
However, researchers found that those defined as slim were bottom in terms of life expectancy, with 33.8 further years predicted among men and 41.1 among women.
Health concerns surrounding the slimmest also eclipsed those of the overweight, with higher risks of heart disease and other illnesses as they age, according to Masato Nagai, a graduate student involved in the research.
“Those who are too slim are reportedly said to be at higher risk of cardiovascular disease and are more likely to develop pneumonia as nutritional deficiency lowers their resistive force,” he said.
Being overweight has long been associated with the increased risk of a raft of diseases, ranging from diabetes to strokes.
However, the health implications of being too slim are also increasingly highlighted in scientific studies.
Last month, Danish researchers found that those with slim thighs measuring a circumference of less than 23 inches were at greater risk of heart disease and death.