I am chuckling about your question re: me venturing outside my comfort zone to try new foods. As our national guide said, "Vietnamese people will eat anything with four legs except a table." I would add two legs as well. And if you think about insects, that would be more legs.
One of my worries before the trip was encountering any menu that listed dog or cat, because I know that they do eat them in some regions of the country. Luckily, they shielded us from that exposure and presented set menus consisting of an appetizer like shrimp or spring rolls, then a light soup, followed by a fish dish and other protein such as chicken or pork in a sauce with rice. Nothing strange, and all was delicious. My only complaint was too much food!
Outside one of our hotels I saw an elderly lady cooking large-looking eggs for sale. Apparently they were duck embryos and people were at little tables, chomping away on those.
The breakfast offerings in the hotels were diverse along with our Canadian-style preference for eggs and toast, but I noticed that meat and noodles were always there, along with pho, the iconic noodle/meat/vegetable soup.
I didn't see any Vietnamese person who was overweight. It might be because their diet tends to be lighter than ours, and they walk a lot (if they aren't on their motorcycles). There is also a prevailing French influence in the food (particularly the bakery items), due to French colonization many years back. People love bahn mi, a baguette-style sandwich filled with pate, meats, and vegetables.
All the walking we did must have counteracted the abundance of food at each meal, because I didn't gain any weight, thank goodness!