Devoid of nutrition; that does not nourish.(adjective)
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Use "nutritionless" in a sentence
"Same reason as why Chinese and Euros add certain "nutritionless""
"When I was a parent, my children did not eat hot dogs and very rarely ate any kind of sugary item — especially something as blatantly nutritionless as marshmallows!"
"Dentist: Did you make sure Johnny ate healthy foods instead of a lot of sugary, nutritionless ones?"