Obesity - as harmful as smoking

Obesity and being overweight in adulthood are associated with large decreases in life expectancy and increases in early mortality, according to the latest research.

The report, published in this month's Annals of Internal Medicine​, has linked the danger to health from obesity to that caused by smoking.

The research finds that people who are overweight at the age of 40 are likely to die at least three years earlier than healthy adults, the same risk as for smokers.

Dutch researchers from the Erasmus Medical Centre and the University of Gronigen in the Netherlands analysed data in the Framingham Heart Study which had 3457 participants from 30 to 49 years of age at baseline.

Mortality rates specific for age and body mass index group (normal weight, overweight, or obese at baseline) were derived within sex and smoking status strata. Life expectancy and the probability of death before 70 years of age were analysed using life tables.

The team found that large decreases in life expectancy were associated with overweight and obesity. Forty-year-old female non-smokers lost 3.3 years and 40-year-old male non-smokers lost 3.1 years of life expectancy because of overweight. Forty-year-old female non-smokers lost 7.1 years and 40-year-old male non-smokers lost 5.8 years because of obesity.

They also assessed obese smokers. Obese female smokers lost 7.2 years and obese male smokers lost 6.7 years of life expectancy compared with normal-weight smokers. Obese female smokers lost 13.3 years and obese male smokers lost 13.7 years compared with normal-weight nonsmokers.

The research showed that body mass index between the ages of 30 to 49 could predict mortality after ages 50 to 69 years, with no relation to body mass during the 50 to 69 year period.

The report concluded that obesity in adulthood is a powerful predictor of death at older ages. Researchers urged for more efficient prevention and treatment as high public health priorities.