Western retailers wishing to expand into China will need a much smaller range of clothes sizes compared to those needed in the US.

According to a study by US consultancy Alvanon, Chinese women have much narrower variances in bust, waist and hips. It found that the US market demands more than double the number of clothes sizes to reach the same population compared with China.

However, due to changes in diet and lifestyle the younger generation in eastern China is growing taller and heavier, bringing it more in line with westerners.

Alvanon chief executive Janice Wang said: “There is an unprecedented retail opportunity in China. As China becomes much more wealthy, we are seeing this huge move to luxury products.”

Marks & Spencer is preparing to open its first store in mainland China