The worldwide cost of obesity is about the same as smoking or armed conflict and greater than both alcoholism and climate change, research has suggested.

研究发现，肥胖问题造成的全球生活成本大约与吸烟或者武装冲突差不多，比酗酒和气候变化都要高。

The McKinsey Global Institute said it cost £1.3tn, or 2.8% of annual economic activity - it cost the UK £47bn. 

Some 2.1bn people - about 30% of the world's population - were overweight or obese, the researchers added.

They said measures that relied less on individual responsibility should be used to tackle the problem.

Lost output

The report said there was a "steep economic toll", and the proportion could rise to almost half of the world's population by 2030.

The financial costs of obesity are growing - for health care and more widely in the economy. By causing illness, obesity results in working days and output lost.

The researchers argued that a range of ambitious policies needed to be considered and a systemic rather than piecemeal response was essential.

A person is considered obese if they are very overweight with a high degree of body fat.

The most common way to assess if a person is obese is to check their body mass index (BMI), which divides your weight in kilograms by your height in metres squared.

If your BMI is above 25 you are overweight. A BMI of 30-40 is considered obese, while above 40 is very obese. A BMI of less than 18.5 is underweight.