We’ve never been more aware of our health. It’s become second nature to monitor every cough and splutter, and to track our temperatures with immaculate precision.
But when it comes to diabetes, our vigilance might be failing. A new study by the University of Exeter found that half a million adults may have type 2 diabetes without realising. The researchers analysed blood samples from 200,000 Britons aged between 40 and 70. They found that 2,000 of them had very high blood sugar levels, indicating they had diabetes, but had not yet been diagnosed with the condition.
According to figures released in 2019 by charity Diabetes UK, 3.8 million people in the UK have diabetes, and 90 per cent of those cases are type 2.
“Type 2 diabetes can be present for many years without symptoms,” says Angus Jones, Associate Professor at the University of Exeter medical school and one of the authors of the study. “The worry about diabetes not being diagnosed for a long time is that people could have significant damage to their body caused by high-glucose.”
This includes damage to the nervous system, damage to the retina of the eyes, heart disease, and hypoglycemia (low blood sugar levels) to name a few.
As winter approaches and the threat of a second wave looms large, this makes for sombre reading. It’s thought that people with diabetes face a higher risk of Covid-19 complications, due to the fact their fluctuating or elevated glucose levels leave them with lowered immunity. This also means they have less protection against getting ill in the first place.
The hidden symptoms
So how do we know if we have type 2 diabetes? Often the symptoms can be “mild and vague”, says Prof Jones - hence why they remain hidden. Two of the most well-known symptoms to look out for are polydipsia and polyuria; in simpler terms, feeling thirsty all the time and needing to go to the bathroom more often.
Often, these symptoms become a “vicious cycle”, says Dan Howarth, head of care at Diabetes UK. “You need the toilet more because the amount of sugar in your blood is too high; it’s not being used for anything, so it’s a waste product. Your kidneys switch on the renal threshold to help get more water out. As a result, you become dehydrated”.
This is why thrush is a common, but often mistaken, sign of diabetes. “You’re weeing out a lot of sugar, so the urine becomes the perfect breeding ground for the bacteria that causes thrush,” says Howarth.
Other symptoms that often go mistaken are fatigue and increased hunger. You feel tired because the muscles aren't getting enough glucose, and hungry as the body tries to increase its uptake of sugar. Often, people with undiagnosed diabetes find that cuts take longer to heal, too. This is because the high levels of sugar in their blood make it “thick and sticky”, preventing the white blood cells from passing through to heal the wound, says Haworth.
Largely, these symptoms go unnoticed because of behavioural factors. “By the time they’re diagnosed with diabetes, 50 per cent of people will already have an existing complication due to the damage that has been done to the small blood vessels,” says Howarth. “They may think that they’re drinking more as it’s a hot day, or they’re tired because of a work deadline.”
Indeed, weight loss - a common symptom of diabetes - often occurs more slowly in type 2 infections than type 1, making it harder to identify. Haworth adds that as roughly 80 per cent of type 2 diabetes is linked to living with obesity, it’s likely that sufferers will see their weight loss as a positive thing.
That's why understanding your risk factor is crucial. According to Prof Jones, old age remains the “strongest risk factor”. However, others include a family predisposition to the condition, ethnicity, a sedentary lifestyle, a history of high blood pressure or heart disease, and being overweight – especially around the middle.
There may be some more secret factors at play too; just last week, a study from Karolinska Institutet in Stockholm, Sweden, found that people with insomnia were 17 per cent more likely to develop diabetes than those without. While it’s important not to panic over such studies, people who are worried can use the ‘Know your risk’ tool on the Diabetes UK website. A routine blood test is where type 2 diabetes is normally picked up, although diabetes screening tests are becoming more common in the UK.
What about pre-diabetes?
Often, people who are at high risk of developing diabetes are said to have pre-diabetes. This is a state categorised by a slightly elevated level of HbA1c - the average concentration of glucose in your bloodstream. The signs can be tricky to spot, particularly as people age.
“The first sign of someone becoming pre-diabetic, and moving towards diabetes, is that they may have a change in their memory, find that their balance isn’t as good as it used to be, or have a fall,” says Professor Alan Sinclair, of the Foundation for Diabetes Research in Older People and lecturer at King's College London.
The good news is that pre-diabetes can be reversible through good diet and exercise. You should aim to keep your weight in a healthy range, aiming for a BMI between 20-25, increase the fibre in your diet while limiting processed sugars and fat.
“It’s crucial to get the right blend of protein, carbohydrates, fats and minerals. It’s also important to get the right composition of vitamins - vitamin D is very important for muscle function,” says Prof Sinclair.
Exercise should be a combination of aerobic, he says, in order to enhance cardiovascular health, and resistance exercise to build up muscle power.
If you do find out that you have diabetes, then the same rules apply; you should eat a balanced diet at regular intervals, quit smoking and get at least half an hour of aerobic exercise a day. Research from Diabetes UK suggests that if you find your type 2 diabetes early enough, you could put it into remission.
“Everyone who is at risk can do things to reduce their risk. You can’t change your ethnicity or your age, but you can make healthier lifestyle choices,” says Howarth.