I wish I could give you a simple answer to this question, but I cannot. It really depends on your activity level, metabolism and your diet overall. If you stick around for a little, I assure you that you will come away from this knowing how much rice you should eat in order to lose weight.
Regardless of where you are at with your weight loss journey, this approach should help. The best way to lose weight is to ensure you that you are satiated with nutritious foods. I emphasize nutritious food, because ultimately the lack of nutrients is what is triggering your cravings. Your body knows to trigger your hunger response when it needs nutrients and/or calories, but it has trouble distinguishing between what foods are nutritious and what foods have calories or both. Now, we cannot just blame our bodies for this mix up. A lot of the food we eat is not natural and is created to taste a certain way, which in turn actually tricks our bodies into craving more of it even though it's devoid of nutrition. Potato chips taste great! Now who can eat the recommended amount of only 6 - 8 chips?
Other foods like cup cakes, candy, bread, pasta, and rice even lack in nutrients as well, but are full of calories (sugar). This spells disaster for our bodies and the bathroom scale and our satiation and energy levels reflect that. Forgive the crude delineation I'm about to use, but I believe it might help make this idea more concrete.
Imagine camping outside in the cold and you need to make a fire. Would you rather fuel your campfire with "paper only" or a combination of "paper and wood"?
Probably the latter because burning wood will produce more heat over time, whereas the paper will burn hot quickly but conversely requiring more and more paper to maintain the campfire. Similarly, this is how your body view those simple carbohydrates as paper. The fiber we should be eating with our food helps to modulate the sugars / calories we need. It slows the burn down and allows us to feel satiated for longer periods of time.
So the question as to how much rice you should eat depends. If are a marathon runner, eating a lot is of simple carbohydrates is exactly what you need, but then again you probably aren't trying to lose weight. For the rest of us, in the weight loss struggle, I would eat enough rice to get the fire burning and to make sure to add plenty of veggies and some protein / fat to ensure my fire stays burning longer. Remember, it's the simple carbs (the things that are metabolized quickly into sugar) that we should cut back on. In nature, those simple carbs are hard to acquire. It's only because we alter our food in such a way that bastardizes our taste buds leaving our bodies out of shape and overweight.
If you are looking for others who are trying to loose weight, check out our weight loss support group. There you can find out what works or doesn't work for others in the battle of the bulge.