Here's what 200 calories of 19 different foods looks like

Portion size is one of the most difficult things for dieters to control and past research has shown that the many people wildly underestimate how many calories they are eating.

To help, YouTube channel AsapScience has taken an array of foods - from Big Macs and beer to celery and cheese - and shown viewers exactly what 200 calories looks like.

More: Here's what 100 calories of different foods look like in six amazing pictures

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