Whether it is normal to gain 3 kg after eating depends on many factors.

First of all, the food weight and calorie intake per meal are important factors affecting the weight change. If the food intake is high in weight and calories, it may lead to weight gain. However, each person's height and weight are different, and the amount of nutrition and food required is also different. Therefore, whether a meal is normal or not can not be judged simply by its weight or heat.

Secondly, digestive and metabolic functions will also affect weight changes. Even if you eat the same amount of food, different people may have different weight reactions. If a person's digestive and metabolic functions are weak, it may lead to food staying in the body for a long time, thus gaining weight.

In addition, the ratio of fat to muscle in the body will also affect the weight change. If someone has a high proportion of body fat, even eating a meal may lead to a significant weight gain.

To sum up, it is normal to eat a meal and gain 3 pounds, which needs to be judged according to personal circumstances. If the weight is within the normal range, don't worry too much; If the weight has exceeded the normal range, it is suggested to adjust diet and increase exercise to control the weight gain.