No. Reheat cooked rice only once. UK government food safety guidance says you should never reheat rice more than once. Even the first reheat is only safe if the rice was cooled quickly and kept in the fridge.
The risk doesn’t come from heating the rice itself. It comes from the time rice spends warm between cooking and eating.
Why rice is riskier than other leftovers
Uncooked rice often contains spores of a bacterium called Bacillus cereus. Cooking doesn’t kill the spores. When cooked rice sits at room temperature, they wake up, multiply and make toxins.
The toxin that causes vomiting survives heat. Microwaving it until it’s steaming hot won’t destroy toxins that have already formed. That’s why “just heat it really well” doesn’t fix rice that was left out too long.
Each round of cooling, storing and reheating gives the bacteria another chance to grow, so the advice is to reheat once.
How to keep leftover rice safe
- Cool it fast, ideally within an hour. Spread it out in a shallow container or on a tray so it loses heat quickly.
- Refrigerate it at 40°F (4°C) or below as soon as it’s cool.
- Eat it within 24 hours, as UK guidance advises. US guidance allows 3 to 4 days for refrigerated leftovers in general, but rice is one food where the shorter limit is the safer choice.
- Reheat only the portion you’ll eat, until it’s steaming hot all the way through (165°F / 74°C).
- Don’t put reheated rice back in the fridge. Throw away whatever is left.
Reheating rice that was frozen
Freezing pauses the clock. Freeze rice within an hour of cooking it, in flat bags or small containers. Then you can thaw it in the fridge (or reheat it straight from frozen in the microwave) and eat it right away. The same once-only rule applies.
Signs of food poisoning from rice
B. cereus food poisoning usually comes on fast, with vomiting or diarrhoea. It typically clears up within about a day. Contact a doctor if symptoms are severe, last longer, or if the person is very young, elderly, pregnant or has a weakened immune system.
Quick answers
Is it the microwave that makes reheated rice unsafe?
No. Any reheating method is fine. What matters is how long the rice sat warm before it went in the fridge.
What about fried rice from a takeaway?
The same rule applies. Refrigerate it as soon as you get home, eat it the next day and reheat it once.
Can I eat leftover rice cold?
Yes, if it was cooled quickly and refrigerated. Eating it cold doesn’t add risk. The storage steps above are what matter.
Sources: GOV.UK, Home food fact checker (rice section); USDA Food Safety and Inspection Service, Leftovers and Food Safety.