Eh, rasa pahit di tekak ni memang uncomfortable! Usually it's either reflux, meds side effect, atau oral health issue, kita mesti tau dulu apa cause-nya sebelum change diet, so better check with your doctor okay. Dalam meantime, a few of my mum friends yang experience this cakap avoid very spicy, acidic, atau oily food dulu, dan minum plenty of water with plain meals. Hope it settles soon!