Asians have been eating rice and other grains for several hundred years, and started to have high rates of diabetes only in recent decades ("Diabetes: The rice you eat is worse than sugary drinks"; May 6).

Westerners do not eat much rice, yet the incidence of diabetes is rising very rapidly in their societies.

It seems that rice alone has not been a problem.

Dr Robert Lustig, a major researcher on the harmful effects of sugar, found that obese children with at least one chronic disorder, such as high blood pressure, improved their health dramatically within nine days when sugar was taken off their diet.

This occurred even though the children continued to receive the same number of calories.

Beyond diabetes, recent research suggests that sugar - not saturated fats and cholesterol - is a leading cause of heart disease, as well as being a major factor in the development of cancer.

Sugar is not a traditional food. It entered the Western diet only around 500 years ago.

Since then, average sugar consumption has shot up to about 70kg per person per year. This sharp rise in consumption corresponds to a sharp rise in major degenerative diseases.

This suggests that sugar is the main culprit, rather than rice.

Richard Seah Siew Sai