Back in November, Full Fact was asked by Men’s Health magazine to take a look at the numbers behind the Government’s ‘Obesity Call to Action’. It had been reported in the press that the Department of Health had asked people to cut out a third of a cheeseburger per day to tackle a growing weight problem.
Our research was used as part of a feature on obesity in this month’s edition, while the full factcheck is below.
If you would like to commission some work from Full Fact, please contact our Director Will Moy on 020 7242 3883 or email@example.com
Two thirds of British men are overweight or obese, and according to the NHS waistlines have been growing steadily for over a decade. Prime Minister David Cameron hit the headlines last month by indicating that he would consider a ‘fat tax’ to encourage us to eat healthier food.
In the meantime, his Government has published an ‘Obesity Call to Action’ which according to the Department of Health represents a “new national ambition for reversing the tide of excess weight in England.”
As part of this ‘Call to Action’, the Department claimed that as a nation England needs to shed five billion calories from its collective daily diet. Helpfully, it explained that this “represents 16.9 million cheeseburgers” or as some newspapers noted, one third of a cheeseburger for every English citizen.
But why five billion calories? Does this represent the weight of scientific opinion, or is it simply a media-friendly round number?
The press release from the Department of Health explains that on average adults consume 10 per cent more calories than they need.
According to the Government’s Scientific Advisory Committee on Nutrition, on average a man requires 2,605 calories per day to maintain a healthy body weight, while women require 2,079 calories.
So England’s 25.1 million men and 26 million women are consuming 260.5 and 207.9 calories too many each day respectively. Put another way, we collectively consume 11.9 billion excess calories per day, more than twice the reduction target set by the Department of Health.
So while 16.9 million cheeseburgers sounds like a lot – and we’re assured that it is enough to cover all 20 Premiership football pitches – the question is actually why the target is as low as it is.
We put this to the Department, who told us that while their five billion figure was drawn up “in line with the advice they had received” the target represented the reduction needed to “stop obesity becoming more of a problem” rather than to eradicate it entirely.
How much weight needs to be lost?
If we divide the 5 billion calorie reduction target equally among England’s 51.1 million citizens, on average we would need to cut 98.7 calories each from our daily diets.
Back in August, US researchers published an article in the health journal the Lancet which studied the relationship between the amount of energy we consume and the weight we gain and lose.
Its lead author, Dr Kevin Hall, told Full Fact that if the Department of Health’s target is reached we could expect to see four kilograms shed from the average waistline.
He explained: “A reasonable rough approximation is that every 24 calories per day decrease of energy intake will lead to about 1kg of weight loss with roughly half of the loss occurring within one year and 95 per cent of the weight loss occurring in three years.”
If however the entire five billion calorie reduction is shouldered by the 60 per cent of adults who are overweight, then each weight-watcher would need to lose approximately seven kilograms on average for the Government to meet its target.
Officially, a person is obese if they have a body mass index (BMI) of 30 or more, while you are considered overweight if your BMI is over 25.
BMI is calculated by dividing your weight in kilograms by your height squared (kg/m2). The average BMI for men and women in England is 27, and the mean weight of a man is 83kg, while women weigh on average 70.3kg.
If we were to knock 4kg from these values and divide them by the square of the average height (1.75m for men and 1.62 m for women), we can calculate what the average BMI would look like if the Government’s ‘call to action’ proves successful. It would fall to 25.5 kg/m2 for both men and women.
This is roughly the level it was at in 1993, when 57.3 per cent of men and 48.6 per cent of women were overweight or obese. If the Government’s strategy succeeds, a return to 1993 levels would mean 6.2 per cent more men and 8.1 per cent more women would record healthy BMIs.
To reverse 18 years of expanding waistlines by 2020 is clearly an ambitious target for the Government to set itself, but the five billion reduction in daily calorie intake demanded by the Department of Health would not in itself eradicate the ‘obesity epidemic’.
The bad news for overweight men and women is that they may need to cut out more than just one third of a cheeseburger to achieve a healthy weight.