It’s not just fat people. The slim and healthy can get diabetes, too
Lorraine Fearn leads an active lifestyle, but suffers from Type 2 diabetes
Most people associate type 2 diabetes with obesity — gorging on fatty foods and doing little or no exercise.
This was confirmed last week by the news that obese people put on a strict 600-calorie-a-day diet were able to reverse the condition.
But while there is no denying being significantly overweight is a key risk factor, one in five with the condition is not obese, with many leading healthy lifestyles.
The problem is that the stereotype of the type 2 diabetes sufferer means that as many as one million people may be going undiagnosed simply because they do not believe they are in a high-risk group.
Experts warn that invisible internal fat around vital organs could be placing this group at risk.
Type 2 diabetes is one of the greatest health care challenges facing Britain.
The cost to the NHS of treating the 2.5 million people diagnosed with the condition is £3.5 billion a year.
And this is set to balloon, with the number of those affected predicted to double over the next ten years.
Just this week, a new report revealed more than 350 million people worldwide have the condition.
Many of those will be people such as Lorraine Fearn, who is anything but the ‘typical’ type 2 sufferer.
She is not obese (at 5 ft 4 in, she weighs 10 st 9 lb), she leads an active lifestyle — she walks for half an hour four times a week and is a keen gardener — and has a healthy diet of fish, vegetables and cereals.
Yet for the past five years, the 64-year-old retired factory worker from Yeovil, Somerset, has had to take daily tablets to control her blood sugar levels following her diagnosis with type 2 diabetes.
Her late mother, who weighed just 7 st, was diagnosed at the same age as Lorraine and her mother’s brother also suffered, despite being over 6 ft and very slim.
In fact, it seems a disease associated with being seriously overweight has blighted her family for generations, despite their low-risk profile.
‘My grandmother also had it and I’m sure her father did as well, because when I was young he went blind and had a leg amputated,’ says Lorraine, referring to two of the more serious complications of poorly managed diabetes.
‘There is a perception that type 2 diabetes is all about obesity. But not all of us are fat.’
Ten per cent of diabetes cases are due to type 1, a different condition that has nothing to do with lifestyle and is thought to be brought on by a malfunctioning immune system, usually in childhood.
Type 2 accounts for the remaining 90 per cent.
According to the charity Diabetes UK, at the current rate of increase, the numbers affected in Britain will rise to four million by 2025.
However, experts say a major cause for concern is that people do not realise their symptoms — such as increased thirst, frequent urination or fatigue — are due to hidden diabetes.
The cost to the NHS of treating the 2.5 million people diagnosed with Type 2 diabetes is £3.5 billion a year
In both types of diabetes, the body loses its ability to make use of glucose, a type of sugar that is released when we eat food, which is then turned into a source of energy for the muscles.
To get into the muscles, glucose needs insulin, a hormone produced by the pancreas. Insulin acts a bit like a key that unlocks the door into muscle cells, so that glucose can be taken on as fuel.
Type 2 diabetes is caused when excess fat interferes with the mechanism of the lock. The pancreas senses the insulin it is producing is not being used effectively and tries to compensate by making even more of the hormone.
This can go undetected for years until the pancreas becomes exhausted and can no longer produce enough, or any, insulin.
As glucose levels rise, circulation starts to suffer and blood vessels can be irreparably damaged. Left untreated, type 2 diabetes can raise the risk of heart attacks, blindness and amputation.
But some experts fear aiming diabetes warnings only at those who are overweight has fooled many into thinking they are not at risk.
When doctors assess a patient’s risk, they test for impaired glucose tolerance — a sign that blood sugar levels are higher than normal — and measure their body mass index (BMI).
This is a calculation that takes account of their weight compared to their height. According to Diabetes UK, anyone with a BMI score of 30 (officially obese) is classed as at risk and in need of lifestyle changes, such as a healthy diet and more exercise. An example would be a man who is 5 ft 10in and weighs 15 st.
But BMI doesn’t measure actual body fat levels. This is why fit rugby players can be classed as obese — they are large, but much of that bulk is muscle, not fat.
Instead, a more accurate indication of diabetes risk is what doctors call visceral fat — hidden fat that lies around the heart, liver, kidneys and pancreas.
According to the charity Diabetes UK, at the current rate of increase, the numbers affected in Britain will rise to four million by 2025
A person who appears to be relatively slim can have high levels of undetected visceral fat, which could play a key role in the development of diabetes.
The best indication doctors have is a pot belly, which points to a build-up of fat in the abdomen.
‘BMI does not tell you the whole story and it’s just as important where the fat is on your body,’ says Julian Halcox, professor of cardiology at the University of Cardiff.
‘Studies show some people can have a normal BMI, but a higher proportion of body fat than you might expect from looking at them.
‘And some people who have even a moderate build-up of fat may be more susceptible to a greater degree of insulin resistance (a pre-diabetic state) than others.’
Dr David Haslam, chairman of the National Obesity Forum, says: ‘At the moment, if BMI is just under 30, doctors are encouraged to say: ‘‘That’s good. We don’t have to do anything just yet.’’
‘What we should be doing is telling them that if they’ve got any excess fat at all round the waistline, that’s a warning sign.
‘Type 2 diabetes is on the increase and when I started out 20 years ago it was rare to diagnose someone with it. Now, I see a new case every couple of weeks.
‘It used to be unheard of to see it in anyone under the age of 40. The other day, I diagnosed a young man who was just 20.’
Dr Haslam is concerned the greater incidence of the disease may remove the fear factor.
‘Everyone knows someone who has ‘‘a touch of diabetes’’. But because treatments are so good these days, they may not see it as that big a problem. But the risks (heart disease, blindness and limb loss) are as great as ever if you don’t get it treated early.’
But there are concerns that there is an over- reliance on drugs rather than lifestyle changes.
In a damning editorial a year ago, The Lancet described the global diabetes epidemic as ‘a largely preventable disorder’ that was nothing short of a ‘public health humiliation’.
It warned there was an over-emphasis on research into drugs to drive down blood sugar levels and too little on lifestyle changes that could be just as effective.
Indeed, a report last week revealed that slashing calorie intake to just 600 a day reduced symptoms to such an extent some of the diabetic volunteers no longer had to take medication.
However, the team warn such a drastic diet should be followed only under medical supervision.
Figures from the NHS Information Centre show spending on diabetes drugs rose 40 per cent to £650 million a year between 2005 and 2010.
Dr Haslam says there is a danger some patients rely on drugs to keep their diabetes under control and neglect lifestyle advice.
Lorraine does both — she takes metformin every day and eats a healthy diet based on cereals, fish, vegetables and salad.
‘My diet has always been pretty healthy. When I was young, my father grew all our vegetables and kept his own chickens,’ she says.
‘I have regular check-ups and have never been told I am overweight. I think it’s misleading when people only talk about obesity causing diabetes.’