What Causes Dizziness Post Food Intake?

I am a 47 year old Indian woman. I am around 20 kg overweight. I suffer from Hypo-thyroidism, which is under control right now, with medicine and yoga. For the past 2 days, my head spins for a few minutes immediately after breakfast and dinner. It goes away after I lie down for some time. I got my BP checked 12 hours back. It is 105/80.