I'm trying to decide if I want to go for full Ironman at some point, but the nutrition part...

Last August I did 70.3, I feel as I could of faired a little better with better nutrition during race...but I finished and had an amazing time!

any other triathletes? When doing long training segments, what do you eat/drink along ride or run?

I'm a triathlete...or was, but will be again. I had back surgery in December 2015 and haven't been able to run since. It's because of my back i ended up with WLS. I hope that I'll one day be able to do it again.

I eat low carb or keto when I was training and racing. worked wonders. Gave me plenty of fuel. I'm not super fast, but my half marathon time is 2:14 on keto. I usually eat nuts, cheese during training and race, had an early breakfast with eggs and bacon, avocado, cheese.

That was before wls though.

I just did my first IM 70.3 in June. I trained using Infinit & Tailwind on the bike, along with Honey Stinger gels and Huma gels. The liquid nutrition always upset my stomach and the gels ended up in a nasty ball jammed up under my rib cage. Lots of fun coming out of T2. Ugh! I have Lap-Band, so certainly have different challenges. There is a girl I found on FB that blogs her WLS to Ironman journey -- Elle's Journey To Good Health.