Scientists said, why run the risk of dying people with excess and lack of weight
Excessively high and excessively low levels of body mass index (BMI) are associated with increased risk of death from almost all major causes, with the exception of road accidents.
A study published October 31 in the journal The Lancet Diabetes and Endocrinology and conducted by researchers from the London school of hygiene and tropical medicine (London School of Hygiene and Tropical Medicine) showed that too high or too low BMI, is associated with increased morbidity from a number of common diseases.
Lead author of the study, Bhaskaran Krishnan (Krishnan Bhaskaran), noted that they found important relationships between BMI and most causes of death.
BMI is a key indicator of health. We know that BMI is associated with risk of death in General, but still held surprisingly few studies of mortality from specific causes. We have filled this gap, to help researchers, patients and physicians better understand the fact that, both insufficient and excess weight can be associated with diseases such as cancer, respiratory disease and liver disease – says Bhaskaran.
BMI is determined by dividing a person’s weight in kilograms by the square of height in meters. The indicator is measured in kilograms per square meter (kg/m2)
The study authors found that a BMI from 21 to 25 kg/m2 is associated with the lowest mortality rate. They also found that a BMI outside this range is associated with almost all causes of death, not only against the most common diseases. And this means that the BMI that is above or below the optimum range leads to an increased risk of mortality.
The study, which analyzed data 3.6 million and 367 512 deaths, showed that obesity (BMI = 30 or above) associated with an increased risk of two major causes of death from heart disease and cancer.
BMI above 25 is associated with most types of cancer, mostly diseases of the cardiovascular and respiratory systems, as well as diseases of the liver and kidney, said Bhaskaran.
The researchers also found that obesity reduces life expectancy by an average of 4.2 years for men and 3.5 years in women and may also contribute to other chronic diseases, including respiratory diseases, liver diseases and diabetes.
British journal of Cancer reported in April that obesity is associated with 7.5% of cases of cancer in women in the UK.
The study also showed that underweight, not surprisingly, is associated with many causes of death and diseases, including dementia, Alzheimer’s disease, cardiovascular disease and suicide.
However, Bhaskaran noted that the study was about the relation of low BMI and mortality worn by observant nature, as it was not clear whether the low weight is the direct cause of the disease or a symptom of poor health in General.
He also acknowledged certain limitations of the study, including the lack of data on diet or physical activity level of participants.
However, he noted that the results confirmed the importance of maintaining BMI in the range 21 to 25.
In particular, the results showed that the lowest risk of death from cardiovascular disease associated with BMI at 25 kg/m2, and each additional 5 kg/m2 associated with an increased risk of death by 29%.
The lowest risk of cancer death was recorded at BMI 21 kg/m2, with every additional 5 kg/m2 weight loss was associated with an increased risk of death by 13%.