How "low carb" of a diet are we talking?
If you're going the route of a stricter low-carb diet, neither may be suitable unless in very small portions. Most of the carbs from these diets generally come from vegetables.
If you're just looking to eat less carbs because you feel you're getting too many, subbing oatmeal for rice isn't unreasonable, but eating an appropriate sized portion of rice isn't unreasonable either. My diet is generally lower-than-Spark-recommend carb (but not really "low carb") and eating rice and oatmeal, even in the same day, usually won't get me close to my minimum recommended carbs.
Do something everyday that your future self will thank you for.
| current weight: 179.8