Sweet-toothed Brits have one less excuse for taking their morning tea with several spoons of sugar. They and other Europeans are among the most sugar-sensitive people in the world, a new genetic analysis concludes.

The vast majority of people in the UK, France, Italy and Russia boast a tandem of genetic variations in a sugar-sensing gene that allows them to detect trace levels of sweetness.

Around the world, populations that live at northern latitudes carry these genetic variations at far higher frequencies than tropical-living peoples,

Although the gene variants were commonest in Europeans, they were also widespread in Japanese, Palestinian, Han Chinese and other Middle Eastern and Asian populations. Low-sensitivity variations were most prevalent among the several different African populations that the team examined.

An even bigger puzzle is why the low-sensitivity variations are more common among Africans. "The straight answer is we don't know