First, it depends on what kind of tofu, Japanese tofu, rice fat tofu, tender tofu or brine tofu, or northern tofu and fried tofu. That depends on whether you only eat this all day or whether you want to eat it with other foods. The third depends on how much you eat. A normal adult needs 2000 calories a day. If you want to lose weight, you need to control it within 1000 calories. If you eat too much tofu, you can't eat anything else, so you won't get fat. If you are afraid of being fat, you must never eat after 6 pm. If you are in a hurry to lose weight, you can't eat after 4 pm. Have fun.