We can tell them ,we can persuade them ,we can explain them that to think about the poor people who are not able to afford food and are starving and you here is wasting the food ?What a shame. If you would tell like that then they will think and try to change their habits.
 In a country like India where people are starving to death,wasting even a plate of rice is equal to killing atleast 3 people.We should make sure to order food in small quantities so that least amount of wastage is done.Moreover,consuming food from restaurants regularly can lead to serious gastrointestinal disorders as well as obesity and common ailments like diarrhoea,constipation,etc.Hence, when in a restaurant we should order food in limited quantities and eat food made at  home more often.
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