They’re great meal-prep containers, too.

Before you reheat tonight’s leftovers, it helps to know what actually matters when it comes to plastic food containers, especially as questions about microplastics continue to grow.

While it’s generally OK to store food in plastic containers labeled with a 1, 2, 4, or 5, you should try to use glass. Plastic marked with a 3, 6, and 7 should be used minimally around food to limit ...