What Causes Choking Sensation And Breathlessness While Swallowing Food?

I m a 46 year old male. Non Smoker in pretty good physical health. Over the last 6 month s I ve developed a problem that s getting more annoying. While swallowing the 1st real food during the 1st meal of the day, I experience a moment of breathing difficulty. To me, its not choking or difficulty swallowing. It just feels like Ive lost my breath. It s that 1st or 1st couple of bites of food. It seems to be worse with a sandwich or some sort of bread. Once I get threw this initial problem, it s goes away and I m good for the rest of the meal. Lately it seams to be happening more frequently. About a year ago, if I ate late and/or ate Italian or Mexican I might wake up gasping to catch my breath because of reflex. This went away a little while before these new symptoms started. I do drink about 2 Diet Mtn Dews a day and Have done this for a LONG time. I used to drink a lot more of them but cut back to 2 about a year ago to see if it helped alleviate the a for mentioned reflex symptoms. I felt that it had but i m wondering about the new symptoms.