It depends on the case; there is no single guideline.
Precautions
Cool/reheat rice with good hygiene (Bacillus cereus)
Effect by goal · level of evidence
Resistant starch / glycemic index (mechanistic)
increases resistant starch (mechanistic)Lowlaboratory study (A)
Cooking rice and cooling it (refrigerator or freezer) increases its resistant starch: the longer and colder, the more retrogradation and the more resistant starch, which is associated with a lower glycemic index. It is a laboratory study of the starch, not a trial of eating it: promising, but the real glycemic effect in people still needs to be confirmed.
⚠️ cool/reheat rice with proper hygiene (Bacillus cereus)
Findings
Resistant starch / glycemic index (mechanistic) — increases resistant starch (mechanistic) (Low, laboratory study). Cooking rice and cooling it (refrigerator or freezer) increases its resistant starch: the longer and colder, the more retrogradation and the more resistant starch, which is associated with a lower glycemic index. It is a laboratory study of the starch, not a trial of eating it: promising, but the real glycemic effect in people still needs to be confirmed. 36826312
Information, not medical advice. Prescription drugs require a doctor.
Information, not medical advice. Scientific evidence reflects the quality of the studies.