You can lose weight. Although oatmeal itself is high in calories, its starch content is much lower than that of rice. In this way, the probability that calories are converted into fat is low, so there is no saying that you will gain weight. There is also oatmeal with strong water absorption, and people who don't eat much will also feel full, thus achieving the effect of losing weight.
Oats contain a high proportion of dietary fiber, which can help the intestine absorb water, cholesterol and impurities, accelerate intestinal peristalsis, reduce energy absorption, and then let you lose weight.