People who use monosodium glutamate (MSG) to enhance the flavour of their food are more likely to be overweight or obese than those who do not, even if they have the same total calorie intake and do the same amount of physical activity.

Such is the claim of a study by the University of North Carolina in the USA and published in the journal Obesity.

More than 750 Chinese men and women between the ages of 40 and 59 from rural villages took part in the study and roughly 82 per cent of them used MSG in their food.

The users were divided into three conditions based on the amount of the product they used.

It was noted that the third who used the most MSG were almost three times more likely to be overweight than their non-using counterparts.

The researchers elected to study people from the rural locations due to the fact that they used very little commercially processed food, but many regularly used MSG in the preparation of food.

Dr Ka He, assistant professor of nutrition and epidemiology at the academic institution's school of public heath, said: "We saw this risk even when we controlled for physical activity, total calorie intake and other possible explanations for the difference in body mass.

"The positive associations between MSG intake and overweight were consistent with data from animal studies."

According to the European Food Information Council, in the European Union, monosodium glutamate is classified as a food additive with the number E621.

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