Interpreting “after having food” as immediately after eating (which may be unfair to you!) then the American Dental Association disagree with you:
> Brushing Right After Eating
> If you feel the need to clean your teeth after eating or drinking, wait at least 60 minutes before brushing—especially if you have had something acidic like lemons, grapefruit or soda. Drink
water or chew sugarless gum with the ADA Seal of Acceptance to help clean your mouth while you are waiting to brush.
> Brushing Right After Eating
> If you feel the need to clean your teeth after eating or drinking, wait at least 60 minutes before brushing—especially if you have had something acidic like lemons, grapefruit or soda. Drink water or chew sugarless gum with the ADA Seal of Acceptance to help clean your mouth while you are waiting to brush.
https://www.mouthhealthy.org/en/brushing-mistakes-slideshow