Apparently, being overweight or underweight could possibly take away four years off the life expectancy of an adult, a study in a Lancet journal suggests.
The report involved nearly 2 million people who were registered with doctors in the UK and is considered to be one of the largest of it’s kind.
Researchers found out that, after the age of 40, people at a high end of the healthy Body Mass Index (BMI) range showed the lowest risks of dying from a disease. But people at the top and at the bottom ends of the BMI index risked having comparably shorter lives.
A “healthy” BMI score is said to be in the range from 18.5 to 25.
Most doctors say that it is the best method they have of working out a person’s obesity because the BMI is accurate and simple to measure. The study, which was published in the Lancet Diabetes and Endocrinology, showed that life expectancy for obese men and women was 4.2 and 3.5 years as compared to people in the entire healthy BMI range.
The difference for underweight men was 4.3 years and that for underweight women was 4.5 years. The study was carried out by associating the BMI with all causes of death categories, excluding categories like transport-related accidents, and including categories like cancer, cardiovascular diseases, and respiratory diseases.
However, not everybody in the healthy category is at the lowest risk of disease, as the author of the report, Dr. Krishnan Bhaskaran explained. He said that for most causes of death the researchers found that there was an ‘optimal’ BMI level, with the risk of death growing with both below and above that level. At BMIs below 21, they observed more deaths from most causes, compared to that with the optimum BMI levels. However, this might also be due to the fact that low body weight can be a cause of underlying ill-health.