It's okay. You won't get fat. Spleen governs muscles. If you have spleen deficiency, your body will become tighter than before. But the spleen needs nourishment. I suggest that you pay attention to medication while taking Chinese medicine. Be punctual for three meals, don't overeat, it's best to eat seven minutes full, eat less greasy and irritating food, exercise properly, don't stay up late, and go to bed before eleven o'clock at the latest. As long as you can do this, you won't be fat, but you may be thinner.