eli5: There are labels on certain products saying “x product was produced in the same factory as y product” where y product contains an allergen. Why does it matter that both products were made in the same factory?

Question

eli5: There are labels on certain products saying “x product was produced in the same factory as y product” where y product contains an allergen. Why does it matter that both products were made in the same factory?

In: 0

Answer 1

The are keeping people with severe allergies safer because they do not guarantee there is not residue from the allergen. For example made peanut butter then sesame butter.