Mei Mengzhen knew the reason: all the stuff in Xiyuan belonged to the space, so after eating food from the space, the impurities in the human body got washed away. With fewer impurities, naturally you'd weigh less. It's the same reason why she never gets fat—she drank Spiritual Spring Water, so her body had absolutely zero impurities.
But of course she couldn't just explain it like that, so Mei Mengzhen said, "It's just that our ingredients are top-notch. All-natural, totally pollution-free—you can eat them without worrying, and you don't have to stress about gaining weight at all. Brother Chengnan doesn't go to Xiyuan much, but you really should go more often. No offense, but every time you guys come, you only order from the menu. Actually, it's our staff meal that's the real deal. Next time, Brother Chengnan, you gotta try it."
