It's estimated 100,000 Kiwis already have undiagnosed type 2 diabetes. Photo / Getty Images
Could you be walking around with an undiagnosed metabolic condition?
Chances are, the answer is yes — and it could have the potential to shorten your life.
I'm talking about type 2 diabetes.
Before your eyes glaze over I should point out one in four of us is thought to have its precursor — prediabetes — and many of those people don't know it.
Lots of us are walking around with a ticking time bomb of potential health problems.
On top of that, it's estimated 100,000 Kiwis already have undiagnosed type 2 diabetes.
Perhaps for this reason, type 2 diabetes is described by Diabetes New Zealand as "insidious"; it isn't usually diagnosed until up to 12 years after hyperglycaemia (abnormally high blood glucose) develops.
At that point it's a lot harder to do anything about it. So how can we know if we might be undiagnosed?
There are some risk factors, and some signs to look out for.
If you are overweight and over 40, you should be thinking about getting checked — especially if you have extra weight around the middle.
Those of Māori, South Asian, Middle Eastern or Pacific island descent are at a higher risk.
High blood pressure and diabetes in the family, or having had high blood glucose during pregnancy, are also red flags.
Symptoms to watch for include fatigue and weakness, excessive thirst and frequent urination.
If you get infections often that are slow to heal, it can be a symptom, as can unexplained weight loss, eyesight problems and frequent hunger.
If any of that strikes a chord, a good place to start is the Diabetes New Zealand website, where there's a "know your risk" quiz.
If that produces a high score, a visit to the doctor and a simple blood test can find out what's going on.
The good news is that type 2 diabetes — like heart disease and obesity — doesn't just inevitably happen as we age.
It's related to that dreaded L word, lifestyle.
And we can turn around a diagnosis of prediabetes so type 2 diabetes doesn't develop — making some lifestyle changes can reduce the risk by up to 60 per cent.
The most important step for many people is probably the hardest: weight loss.
Changing what, and how much, you're eating, and upping the exercise — which in itself reduces risk — will help.
There's some evidence that lower-carbohydrate diets can be helpful for weight loss in people with prediabetes.
Experts emphasise whichever way you choose to drop the weight, it has to be a way you can maintain. Put on weight again and you're likely to have the same problems.
And living with diabetes — while possible — is not something any of us wants to do.
The long-term problems of type 2 diabetes are as serious as a heart attack — and even less fun.
• Niki Bezzant is editor-at-large for Healthy Food Guide.
They won't be joining the royal family at Sandringham this year.