Why You Shouldn't Reheat Food That's Already Been Reheated

If you're a fan of batch cooking or meal prepping – both of which are great ways to save time during a busy workweek — or if you have a big take-out order, chances are you will be spending the rest of your week reheating leftovers in the microwave, oven, or on the stovetop. Inevitably at some point, you may be looking to reheat something that has already been heated up once. But should you? And just how many times can you reheat something before it's "bad"?

It turns out the answers to those questions are not totally clear-cut. Many sources, including Healthline, warn that leftovers should not be exposed to heat more than once. The concern, according to NHS, is that the more times you cool and reheat food, then the greater risk becomes of exposing yourself to contracting food poisoning. That certainly seems like a valid concern. However, that risk can be a bit mitigated, from a safety point of view, if you reheat your food properly.

The rules seem to be able to be bent if you get your food piping hot, says SBS. It's important to make sure that the dish has been thoroughly reheated to about 165 degrees F, using a food thermometer to measure the center of the plate for an accurate reading. This is a particularly essential step if you are using a microwave to heat up your leftovers, as microwaves have a tendency to heat food unevenly. Even better, take out the food partway through microwaving and give it a good stir to ensure every part gets heated properly, advises BBC. If there are still leftovers, be sure to return them to the fridge within two hours, Healthline further recommends. And if you can't finish those leftovers in four days, freeze them instead.

There are also other concerns besides safety when it comes to whether you should reheat leftovers multiple times. For example, each time you reheat food, it deteriorates in quality — they can dry out or there can be at total change in texture, according to The Kitchn. So, while it may be safe to reheat food more than once, it doesn't mean you should. To avoid these issues, only reheat the portion of food you plan to eat in one sitting.