Typically, weight loss can be achieved by having a negative caloric balance. This simply means you need to spend more calories than you get into your body. Food consumption is the source of all the calories that you get. So, if the caloric content of pomegranates or any other fruits will help you achieve your goal, then they are helpful in weight loss.
Pomegranate can be a part of a weight loss diet, and aid in weight loss, as it can be relatively lower in calories compared to other foods. Per 100g of pomegranate contains 83 calories. This is low compared to more calorie-dense foods, such as processed and packaged junk foods. Pomegranate is also a source of fibre (per 100g contains 4g of fibre), which helps to keep us full, amongst other health benefits.
Overall, pomegranate is a healthy food, too. As long as you are able to fit the calories provided from pomegranate into your daily calorie intake, it can be a good food for weight loss. Other fruits would also work well, too, as they are generally also fairly low in calories.