Singaporeans are sleep deprived. And it's not just the sheer number of hours of sleep that is causing a lack of energy, but also the excess time they are spending at work and online, at least according to a UK study by Sleepseeker.

In fact, of the 15 most tired countries in the world, Singapore tops the list.

The "fatigue score" that each site scored was based on data such as the number of hours and minutes lost from the eight hours of sleep generally recommended and the daily amount of screen time people spent in different locations.

'Most tired' countries:

Singapore

Mexico

Brazil

US

Japan

United Kingdom

New Zeland

Australia

China

Canada

Ital

Switzerland

Germany

France

The Netherlands.

Countries that work more hours per year:

Mexico

Singapore

China

US

New Zeland

Japan

Ital

Brazil

Canada

United Kingdom

Australia

Switzerland

France

Netherlands

Germany.

Mexico is in such a high position in the list, due to its economy that is experiencing a very rapid growth and the population is also having difficulty balancing work and personal life.

Countries where the most time is spent online, per year:

Brazil

Mexico

Singapore

US

Ital

New Zeland

China

Canada

United Kingdom

Australia

Switzerland

Netherlands

France

Germany

Japan.