Excess weight linked to higher risk of death from cancer, heart disease, others

People who are over or underweight may be at greater risk of death than previously expected, scientists say.

London School of Hygiene and Tropical Medicine, United Kingdom (U.K.), researchers analysed data from around 3.6 million people to make the conclusion.

They found having a high Body Mass Index (BMI) – over 25 – is linked to a higher risk of death from every major cause, except transport accidents.

While being underweight was also found to increase the risk of death for conditions such as cancer and heart disease, according to the study.

Lead author, Dr. Krishnan Bhaskaran, said the work is among some of the first in this field.

He said: “We know that BMI is linked to the risk of dying overall, but surprisingly little research has been conducted on the links to deaths from specific causes.

“We have filled this knowledge gap to help researchers, patients and doctors better understand how underweight and excess weight might be associated with diseases such as cancer, respiratory disease and liver disease.

“We found important associations between BMI and most causes of death examined, highlighting that body weight relative to height is linked to risk of a very wide range of conditions.

“Our work underlines that maintaining a BMI in the range 21-25 is linked to the lowest risk of dying from most diseases.”

Body mass index (BMI) is a measure of body fat based on your weight in relation to your height. BMI = (weight in kilogrammes / (height in metres x height in metres))

Measurements: Under 18.5; Underweight 18.5 – 24.9; Healthy 25 – 29.9; Overweight 30 or greater; and Obese 40 or greater.

The report found BMI was linked to death from every major cause except transport-related incidents.

The lowest risk of cardiovascular death was in those with a BMI of 25.

Every five-unit increase in BMI above this was associated with a 29 per cent higher risk, said the report, published in The Lancet Diabetes and Endocrinology journal.

The lowest risk of cancer death was with a BMI of 21 – with every five-unit increase associated with a 13 per cent higher risk.

BMI outside the healthy range was associated with up to several years of lost lifespan, with most of the absolute mortality burden driven by obesity – those with a BMI of at least 30.

The report said the expected age of death for a 40-year-old of healthy weight who had never smoked was 82.2 years for men, and 84.3 for women.

Obesity was associated with knocking 4.2 years off that figure in men, and 3.5 years in women.

Class three obesity – those with a BMI of at least 40 – was associated with shortening life expectancy by 9.1 years in men and 7.7 years in women.

BMI calculators use factors such as age, weight and height to determine whether a person is of a healthy weight.

Also, the impact of obesity and overweight on the U.S. economy has eclipsed $1.7 trillion, an amount equivalent to 9.3 percent of the nation’s gross domestic product, according to a new Milken Institute report on the role excess weight plays in the prevalence and cost of chronic diseases.

The estimate includes $480.7 billion in direct health-care costs and $1.24 trillion in lost productivity, as documented in America’s Obesity Crisis: The Health and Economic Impact of Excess Weight.

The study draws on research that shows how overweight and obesity elevate the risk of diseases such as breast cancer, heart disease, and osteoarthritis, and estimates the cost of medical treatment and lost productivity for each disease.

For example, the treatment cost for all type 2 diabetes cases – one of the most prevalent chronic diseases connected to excess weight – was $1.21 billion and indirect costs were $215 billion.

On an individual basis, that comes to $7,109 in treatment costs per patient and $12,633 in productivity costs.

America’s Obesity Crisis assesses the role excess weight plays in the prevalence of 23 chronic diseases and the economic consequences that result.

To mention a few, obesity and overweight are linked to: 75 percent of osteoarthritis cases; 64 percent of Type 2 diabetes cases; and 73 percent of kidney disease cases.

The findings suggest that more effective weight-control strategies could reduce both the health and economic burdens of chronic diseases, according to co-author Hugh Waters, director of health economics research at the Milken Institute.

“Despite the billions of dollars spent each year on public health programs and consumer weight-loss products, the situation isn’t improving,” Waters said. “A new approach is needed.”

The impact of obesity on chronic disease is not limited to the stress that added weight places on joints and the cardiovascular system.

For example, research indicates that hormones secreted by fat cells may trigger inflammation and increase insulin resistance.

These reactions can, in turn, contribute to greater risk of type 2 diabetes, cardiovascular disease, and some cancers.

Nearly 40 percent of Americans were obese and 33 percent were overweight but not obese in 2016, according to the Centers for Disease Control and Prevention.

The numbers have climbed steadily since 1962, when 13 percent of the population were obese and 32 percent were overweight.

Direct medical costs include payments made by individuals, families, employers, and insurance companies to treat the diseases in question.

Indirect costs include the economic impact of work absences, lost wages, and reduced productivity of patients and caregivers.

The estimates in America’s Obesity Crisis are based on an analysis of data compiled by the Centers for Disease Control and Prevention, the National Center for Health Statistics, the U.S. Agency for Healthcare Research and Quality, and the Bureau of Labor Statistics.

The report relies on the World Health Organization’s definition of overweight as a body mass index of 25 to 29.9 and obesity as a BMI of 30 or higher.

Meanwhile, babies and toddlers given antibiotics are much more likely to become obese, a major study suggests.

A review of more than 300,000 children found that those prescribed antibiotics during their first two years of life had a 26 per cent higher risk of obesity.

The longer that children had been taking the drugs and the more classes of antibiotics they had taken, the greater the risk.

Girls given four or more types of the drugs were 50 per cent more likely to become obese.

Almost three-quarters of all the children studied had been given antibiotics before their second birthday. But of the 47,000 who went on to become obese, nearly 90 per cent had been prescribed either antibiotics or antacids.

Researchers say that these powerful drugs can kill off important bacteria in the gut, which help to regulate body weight.

Dr. Cade Nylund from the University of the Health Sciences in Maryland, senior author of the study, said: “There are too many unnecessary antibiotics being prescribed to infants who may not need them, for things like common colds.

“We have to be careful about medications which might risk obesity because people who are obese in childhood typically increase their weight in adulthood, putting them in danger of high blood pressure, diabetes and heart problems”

Antibiotics have long been linked to obesity and farmers give them to cattle with the express purpose of bulking them up.

The study examined antibiotic and antacid prescriptions for 333,353 children in their first two years and followed their medical records up to the age of eight.

The average risk factor for obesity rose by 26 per cent for antibiotic prescriptions, but by only 1 or 2 per cent with antacids. This is thought to be because antibiotics kill off gut bacteria more quickly.

The survey showed there was a particular risk for boys and for children born by caesarean section, who are believed to miss out on important gut bacteria transferred through the birth canal.

Researchers say there is ‘mounting evidence of unanticipated consequences’ for the particular antibiotics and the antacids they studied, namely proton pump inhibitors (PPI) and histamine 2 receptor antagonists (H2RA).

However, British experts remain sceptical about the study, which is published in the journal Gut.