For some people, it takes years for their high blood sugar levels to result in full-blown diabetes. For others, all it takes is a matter of months.
To find out why, a team of doctors from the National University Hospital (NUH) is embarking on a study that will chart the course to Type 2 diabetes in 2,300 people without the condition.
They will track these volunteers for three years to see if any of them develop diabetes, and study the factors that might have caused it.
The study will comprise 800 people with normal blood sugar levels, and 1,500 pre-diabetics - those with blood sugar levels approaching the diabetic range.
"To our knowledge, this is one of the largest studies that go to this level of depth and breadth... to better understand the risk factors," said Dr Sue-Anne Toh, a senior consultant with NUH's endocrinology division who is heading the study.
To our knowledge, this is one of the largest studies that go to this level of depth and breadth... to better understand the risk factors.
DR SUE-ANNE TOH, a senior consultant with NUH's endocrinology division
She added that the study plans to identify lifestyle factors and other biomarkers - such as certain proteins, for example - that make someone more likely to develop the chronic condition.
The $20 million study is jointly funded by the Ministry of Health and Janssen Pharmaceuticals.
Type 2 diabetes occurs when the body cannot produce enough insulin or use it properly.
Earlier this month, Health Minister Gan Kim Yong announced that his ministry is "declaring war" on diabetes in Singapore.
There are more than 400,000 diabetics in Singapore today, a third of whom do not even know they have the disease.
If untreated, it can lead to complications such as blindness, amputations and heart attacks.
Professor Chia Kee Seng, who is the dean of the NUS Saw Swee Hock School of Public Health, recalled an incident when a diabetic man with a swollen foot went to see him.
The man was completely unaware that a rusty nail was embedded in the sole of his foot, because his nerves had been damaged by diabetes.
"Diabetes is a very silent disease," said Prof Chia, who is an adviser for the new study. "I might be having diabetes right now and I wouldn't even know it... there are no symptoms. It's the complications of diabetes that are the problem."
Those who are interested in joining the study can e-mail the research team at brite_spot@ nuhs.edu.sg. They can also call 9135-4495 or 9131-4490 during office hours.
To be part of the study, they must be between 30 and 65 years of age, and be generally healthy with no history of diabetes or other chronic conditions requiring long-term medication.
Both those with normal blood sugar levels and pre-diabetics can apply.