Meal prepping can save time and reduce food waste, but how long is it safe to keep cooked food in the fridge?
A Threads post warning against storing and reheating leftovers for weeks has sparked questions among Malaysians, with some wondering whether preparing meals for an entire week could put their health at risk.
The post, shared by Threads user @dellniel, claimed that keeping old dishes in the fridge and reheating them could expose people to aflatoxins, which have been linked to liver cancer.
The user urged households to consume cooked dishes within three days and avoid keeping old food simply because they did not want to throw it away.
The warning prompted several users to question whether weekly meal preparation was also unsafe.
“So we can’t meal prep for a week?” one commenter asked.
Another described cooking in large batches, dividing the food into containers and reheating individual portions throughout the week, before asking whether this practice was a cause for concern.
In response, the original poster clarified that the warning concerned food kept in the fridge’s chiller compartment, rather than meals that had been frozen after preparation.
“The keyword is ‘old leftovers’,” the user wrote in Malay.
He added that his concern was about dishes left in the chiller for a week, advising those who prepare meals in advance to store them in the freezer instead.
Some commenters also shared their own habits, with several preferring to cook only enough for each meal to avoid having leftovers.
However, another commenter questioned the link between refrigerated leftovers and aflatoxins, pointing out that the two issues should not be confused.
Aflatoxins are toxins produced by certain moulds that can contaminate crops and food ingredients such as cereals, nuts and spices, particularly when stored under unsuitable conditions.
According to the World Health Organization (WHO), exposure to aflatoxins can damage the liver, with evidence linking them to liver cancer in humans.
However, this does not mean that reheating refrigerated leftovers itself causes liver cancer.
For those who regularly prepare meals in advance, proper storage remains the key to reducing food safety risks.
The United States Department of Agriculture (USDA) advises consuming refrigerated leftovers within three to four days, or freezing them if they need to be kept for longer.
It also recommends dividing cooked food into shallow containers to help it cool quickly and refrigerating it within two hours of cooking. This period is reduced to one hour when the surrounding temperature exceeds approximately 32°C.
Refrigerated food should also be kept at around 4°C or below.
Those preparing meals for an entire week should therefore freeze portions they do not intend to eat within the recommended refrigeration period.
Meal prepping can still be a convenient way to save time and avoid wasting food, provided leftovers are cooled, stored and consumed safely.
