How can i determine if a food allergy is worsening my acne?

Timing: The time between "food allergy" and acne should be within days, no more than weeks.

Not allergy: Food allergy can manifest in multiple ways including skin reactions. However, acne is not a symptom of food allergy. Usual skin reactions to food are hives (urticaria), swelling (angioedema), flare of eczema, and itching. For acne, there are multiple treatments available, but no need to change your diet.