Simply using small plates and self-serving could significantly help reduce weight and fight the growing problem of obesity, a new study suggests. Researchers have found that reducing the diameter of the plate by 30 percent can also cut food consumption by 30 percent.

The study, published in the Journal of the Association for Consumer Research, claims that using small plates to lose weight could be more effective if people are self-serving their portions, as they would tend to serve themselves less. In addition, smaller plates work best if diners are unaware that they are being monitored of their consumption.

The researchers noted that plate size would appear to be less effective or not effective at all on reducing consumption if people realise that they are being watched. This comes from previous studies that have not found an effect of plate size on consumption as research volunteers learned that they were being watched as they ate.

The current findings come from the analysis of more than 50 studies that examined the effects of plate size on food consumption. These studies analysed how plates could reduce consumption by considering conditions like food, plate-type like bowls vs. plates or serving platter vs. plate, portion-size and setting.

The researchers suggest that simply switching to smaller plates can prevent people from overeating, especially in situations where they serve themselves like buffets. In addition, "just changing to smaller plates at home can help reduce how much you serve yourself and how much you eat," said study author Natalina Zlatevska, from Bond University, Australia.