When you look at these four women, what do you think? One runs 100 miles a month; another is a busy mum of two who’s always on her feet; a third is toned and strong from cycling and yoga, while the fourth walks for at least an hour each day.
So, apart from their fitness, what do they all have in common? Startlingly, they have all been labelled overweight — or even obese — by the NHS. That judgment is made on the basis of their Body Mass Index (BMI) calculation, a simple formula that divides a person’s weight by their height squared.
If the resulting number is between 18.5 and 25, doctors consider you ‘healthy’. Anything lower is ‘underweight’, while anything above 25 is ‘overweight’. A reading above 30 counts as ‘obese’. As a result of this calculation, one of these women was told she must urgently lose weight if she wanted to have a baby. Two were repeatedly fobbed off by doctors with instructions to diet, their serious medical conditions going undiagnosed or ignored. The other, previously happy and confident, was made to feel like a failure for being ‘too big’.
And yet a growing number of experts claim that BMI is ‘nonsense’, at best a label based on flimsy pseudoscience and, at worst, a cynical tool exploited by the makers of weight-loss drugs that is contributing to a mental health crisis among women and girls.
So, are you unhealthy if your BMI puts you in the ‘overweight’ category? Or — as these women appear to demonstrate — are we stigmatising normal bodies?
From left to right: LAURA, 30. HEIGHT: 5ft 3in BMI: 27 Goes bike riding and does yoga. SALLY, 40. HEIGHT: 5ft 9in BMI: 26 Busy mother of two who is always on the go. KELLEE, 33. HEIGHT: 5ft 11in BMI: 26 Walks for at least an hour every day. EMMA, 45. HEIGHT: 5ft 4in BMI: 26.2 Runs more than 100 miles every month
The controversy around BMI was reignited last week when TikTok user Regan Ellis challenged her doctor’s assessment of her size 12 body as ‘obese’.
The salon owner posted a video describing her disgust at being instructed to lose 2½ stone — all on the basis of a misreading of her BMI. At 5ft 7in and 11st 12lb, Regan has a BMI of 26, meaning she had only just tipped from a ‘healthy’ BMI of 25 into the ‘overweight’ category.
Nonetheless, the 22-year-old was left in tears when her doctor prescribed weight-loss pills which gave her painful diarrhoea. She says she was ‘mortified’ that the body she’d been proud to show off in beach photos was supposedly a health risk.
When she went back to the doctor, having lost 10lb through unhealthy crash dieting, she was told to lose at least 10lb more. Against guidelines, Regan then started using weight-loss injections meant for people with diabetes as she struggled to lose the weight she’d been told to shed.
‘I’m a UK size 10 — how am I fat?’ she asked her followers. ‘What a complex to give a young girl.’
She added: ‘It makes me realise how dangerous BMI can be . . . the scale needs re-evaluating.’
NHS surgeon Dr Joshua Wolrich, author of the bestselling book Food Isn’t Medicine, agrees. He says the focus on BMI may encourage medics to look at patients as statistics, not individuals.
‘BMI is simply a measure of weight and height. It doesn’t give you any idea as to what that weight is — whether it’s muscle or fat, for example,’ he says. ‘As a population level statistic, [BMI] is not too bad. But when we start using it to judge an individual’s health, it’s not accurate at all.’
Even those who consider BMI useful recognise it as a blunt tool.
Professor John Wass, an obesity expert at the University of Oxford, says: ‘If you’ve got a high BMI, you can be healthy or you can be unhealthy. You also need to know your cholesterol, your blood pressure and that your fasting blood sugar is normal.’
It’s made me worried. I avoid figure-hugging clothes now
No one can dispute that Britons are getting bigger. Figures suggest that 28 per cent of adults in England are obese and health authorities have flagged this as a serious problem, since obesity is implicated in potentially life-threatening conditions, including type 2 diabetes, heart disease and some types of cancer.
But could it also be true that we are labelling many healthy women overweight? Take Kellee Wilkes. At 5ft 11in she is catwalk-tall. Yet her height and weight of 13st 5lb give her a BMI of 26, making her ‘overweight’.
‘I was shocked,’ says Kellee, 33. ‘I’d always thought of myself as slim, but this has changed the way I feel about my body. I avoid figure-hugging clothing I wouldn’t have thought twice about in the past. It’s made me worried about diabetes and if I get out of breath when I’m exercising, I think it’s because I’m fat rather than just exerting myself.’
As a result of this calculation, one of these women was told she must urgently lose weight if she wanted to have a baby. Two were repeatedly fobbed off by doctors with instructions to diet, their serious medical conditions going undiagnosed or ignored. The other, previously happy and confident, was made to feel like a failure for being ‘too big’
The sales executive, from Loughborough, says she is fit and well and doctors have never flagged her blood sugar, cholesterol or any other indicator as a concern. But being officially labelled overweight has caused spiralling anxiety.
‘The BMI calculator says a healthy weight for my height is as low as 9st 6in. So I’d have to lose just under four stone to reach that. It feels impossible — but officially that’s healthy, which makes me doubt myself.’
But should women like Kellee be made to feel like a failure because their BMI is ‘wrong’?
Last year, a report from the Commons women and equalities committee described BMI as ‘dangerous’, blaming it for a rise in body image anxiety. There are even concerns that the calculations behind it don’t work for women — nor for anyone who isn’t of white European heritage.
That’s because BMI was invented in the 19th century by a Belgian statistician, Alphonse Quetelet, who gathered his data on what he considered the ideal weight from French and Scottish men. He made no link with health.
His pseudoscientific calculations were later revived by the U.S. life insurance industry as a quick way to estimate a person’s likely lifespan. Slowly but surely, BMI began to be adopted in medical settings, too — albeit with little evidence to support its use.
Dr Wolrich says Quetelet was ‘just a mathematician doing sums’ and his calculations don’t take into account the rich variety of human bodies. Hence, an athlete might well be considered ‘obese’ according to a BMI calculation, despite having very low body fat and lots of healthy muscle.
Then there’s the fact that men and women have very different distributions of fat and muscle, while experts say the health risks associated with a high BMI start at a lower number in South Asian populations and a higher number in black populations.
The calculation doesn’t work as it should for children or the elderly, either — which leaves a vanishing number of people it does work for.
The thresholds used to determine who is ‘healthy’ and who is ‘overweight’ seem arbitrary, too, says Dr Wolrich. After all, they have been altered significantly since BMI was first used.
In 1997, the World Health Organisation (WHO) lowered the ‘healthy’ BMI cut-off from just over 27 to 25 and most countries, including the UK and U.S., followed suit. The Washington Post reported uproar as 29 million Americans suddenly found themselves branded overweight.
The controversy around BMI was reignited last week when TikTok user Regan Ellis challenged her doctor’s assessment of her size 12 body as ‘obese’. Stock image used
An obesity researcher on the panel that recommended the change in the U.S. even spoke out against it and claimed the WHO report ‘misquoted the data’.
Dr Wolrich says: ‘The research presented to the WHO only found a relationship between BMI and ill health above a BMI of 40 — meaning that they should have raised the cut-offs, not lowered them.’
So why were the limits lowered? One possible, and frightening, answer, offered by Dr Wolrich among others, is that the International Obesity Task Force, a group primarily funded by the pharmaceutical companies behind weight-loss drugs Meridia (Sibutramine) and Xenical (Orlistat), contributed to the WHO report.
‘This is movie-plot stuff,’ Dr Wolrich says. ‘It seems clear to me why these companies may have wanted the thresholds lowered instead of raised.’
The WHO told Femail its 1997 expert consultation on obesity was prepared by the WHO Secretariat, based on research and papers from a variety of experts, including members of the International Obesity Task Force and several others. Several studies have indicated that the ‘healthiest’ BMI value is, in fact, 27 — two points higher than the current threshold and comfortingly close to the average UK BMI of 27.6.
This leads to patients being misdiagnosed or ignored
Yet the ‘overweight’ threshold of 25 is still in use — with very real consequences. Just one digit in the wrong direction can make the difference between being eligible for a joint replacement on the NHS or not, for example. It can also affect access to fertility treatment (a BMI over 30 is the NHS cut-off for IVF).
When Sally Stevens was trying to conceive, her BMI of 26 became a distressing focus. Sally, 40, is 5ft 9in with an hourglass size 12 shape, but doctors repeatedly brought up her BMI as an issue.
‘I was constantly advised to lose weight. I ate very healthily, and there were no other indicators my weight was a problem.’
In the end, Sally conceived her two children, now six and five, without medical intervention — but insecurity about her weight has remained.
She says: ‘I don’t think enough thought is given to the guilt and shame this triggers in a woman. You feel you’re not providing the ‘right’ body for your child and worry you might not get medical help because of it.’
Forget BMI: use these measures instead
BLOOD PRESSURE: An ‘ideal’ blood pressure is considered to be between 90/60 mmHg and 120/80 mmHg.
CHOLESTEROL: Your total cholesterol should be 5 mmol/l or below. HDL cholesterol — also known as good cholesterol — should be 1 mmol/l or above, and non-HDL or ‘bad’ cholesterol should be below 4 mmol/l.
RESTING HEART RATE: This should be 60-100 beats per minute. A resting heart rate lower than 60 is very good.
FASTING BLOOD SUGAR: A normal fasting blood sugar (taken after an overnight fast) should be 3.9 to 5.4 mmol/l (70 to 99 mg/dl). A measurement of 5.5 to 6.9 mmol/l (100 to 125 mg/dl) indicates prediabetes and a diagnosis of diabetes is above 7 mmol/l (126 mg/dl).
Labelling slightly larger women as overweight fuels a dangerous stigma, says Dr Wolrich. He adds: ‘It leads to patients being misdiagnosed or ignored because they’re judged by their weight and that’s used to assume their health, which is incorrect.’
For women like Emma Lonczyk, BMI becomes a red herring that distracts from other problems. At 5ft 4in and 10st 12lb, Emma has a BMI of 26.2 — but until two years ago, she was pushing 15st with a BMI of 35, well into the obese category.
Yet the businesswoman from Staffordshire was perplexed by the figure. She was running more than 20 miles a week and eating healthily, so there seemed no reason for her weight to balloon. Emma, 45, says: ‘Every doctor other than my GP told me — not in so many words — that I was fat and lazy. They clearly didn’t believe I ran 100 miles a month.’
With many of her appointments over the phone due to Covid, Emma feels her BMI became the key statistic by which she was judged. ‘It was vile — I felt horrible. They were relying just on those numbers. It’s quite frightening. Before you even set your foot in the door, they say you need to diet and exercise.’
When she did finally see a doctor face to face, she went ‘with a bag full of running medals. I slapped them on his desk and said: ‘I can’t do any more than I’m doing.’ It turned out she had Pseudo-Cushing’s syndrome, a hormonal issue which came about as a side-effect of her contraceptive pill. The disorder was flooding her body with stress hormones, causing her to gain weight no matter what she did.
Since coming off the Pill two years ago, she has lost 4 st — and today feels the stigma around her BMI was a factor in delaying her diagnosis.
The fact the BMI system was designed with men in mind means it also fails to take into account how a woman’s hormones interact with her weight — as Laura Poole found when she was struggling with irregular and painful periods.
At 5ft 3in with a small waist, and strong from yoga and riding her bike, Laura’s BMI of just over 27 was flagged by her doctor.
‘I have cysts on my ovaries which affect my menstrual cycle, and my male doctor was very dismissive. He looked at my BMI and said one of the things you can do for painful periods is try to lose weight.
In 1997, the World Health Organisation (WHO) lowered the ‘healthy’ BMI cut-off from just over 27 to 25 and most countries, including the UK and U.S., followed suit. Stock image used
‘I dieted by reducing my calories and eating fewer carbs. But then my periods stopped altogether. I didn’t even lose much weight. Maybe a stone — so I would still have been just into the BMI overweight category.’ [The ‘healthy’ range for her height is 7st 6lb to 10st 1lb].
For six months, she was without a period — potentially risking her fertility. When she put the weight back on, her periods returned. Laura, a 30-year-old life coach from Plymouth, was left in no doubt that losing weight was not a healthy choice.
‘Losing my period scared me — it just didn’t feel right.’
One emerging line of thinking is that for some, the ‘set point’ weight — the weight at which we naturally hover, when eating well and exercising sensibly — may always be a little ‘overweight’ according to BMI. This is because we are built to store energy.
The problem remains that BMI has become part of our culture, social as well as medical. Scrapping it would require a major rethink of how we assess health risks — but Dr Wolrich insists a rethink is necessary.
He and Professor Wass believe it is essential to focus on other metrics — such as blood pressure, cholesterol, sleeping, eating and exercising well — to determine health and risk factors.
‘The BMI cut-offs are nonsense,’ says Dr Wolrich. ‘We should be inherently suspicious of anything that parcels us into nice, neat categories that happen to be at intervals of five.
‘That is not how health works. The body is far more complex than that.’