As a young man in the 1960s, Mr Raymond Chu would open soft drink bottles with his teeth, crunch ice cubes, and chomp directly on thick stalks of sugar cane.

It was possibly these habits - and his love of smoking - that caused him to start losing teeth when he was in his 30s, he told The Straits Times ruefully. At age 67, the therapist now wears a full set of dentures on his upper jaw.

"In those days, we didn't really care about dental health," he said. "At that time, most dentists wouldn't do fillings either - they would just pluck out your teeth."

But according to the results from a new study of nearly 5,000 Singaporeans aged 60 and above, Mr Chu is one of the lucky ones.

Researchers found that three in 10 people in this age group have no teeth at all.

This is higher than the average rate in other developed countries, which usually stands at between 17 per cent and 20 per cent, according to clinical associate professor Teoh Khim Hean, who heads the restorative dentistry department at the National Dental Centre Singapore.

Apart from the obvious problems with eating, having no teeth could also put people at higher risk of developing problems such as dementia, or even death.

"There's a link between dental health status and mortality," said associate professor Angelique Chan, executive director of the Centre for Ageing Research and Education at Duke-NUS Medical School.

The study, a collaboration between the two institutions, was published in an international journal earlier this month.

Researchers found that women in particular are more likely to lose all their teeth. Part of the explanation, said Prof Teoh, is likely to be that women traditionally get more cavities. In addition, their hormones put them at higher risk of tooth loss.

However, most toothless people have dentures, which means they can eat properly and are less likely to suffer from poor nutrition.

Prof Teoh explained: "When you don't have teeth to chew with, you tend to take a soft diet and eat less meat and vegetables, which could lead to nutrition issues."

But even with prosthetics like dentures readily available, there is nothing like the real thing.

This is a sentiment that Mr Chu shares.

"Of course, having your normal teeth is much better," he said. "When you chew with dentures, the sensation is just not there."