This is a very interesting subject with a lot of people's good advice, great stuff.
I'm not a cook by any stretch of the imagination, and neither is a friend of mine who is an avid backpacker, and he told me just to go to YouTube and search: "cheap food for backpacking". So I watched all of those, and basically do that type of food. I use freeze-dried low-fat milk for my cook cereal. I did take eggs once because I found they're good for about 24 hours not in the fridge. I try to find stuff high in carbs for energy which that cheap Walmart method is pretty good at finding that source.
Yes, that freeze dried food is too expensive. I do not like it, either. One thing about the high carb foods for backpackers. That is meant for being on trails for days at a time away from sources of other food. When cycling over the road long distances there are usually always stores and restaurants. You do not need that Wal Mart stuff. You need fresh fruits and vegetables, live vitamins, minerals, enzymes and protein and more. Man cannot live on carbs alone. You will need real nutrition. Backpacker food may be good for a carb load, but be sure to get the other foods regularly.
Did you know you can starve to death if you ate nothing but protein foods like lean meat? I watch that Surviving Alone contest show, and the people they put on are really good, and considered professionals at surviving alone in the wild. The contest is who can last the longest, and they check your weight every week and if you lost too much weight and are in the danger zone you're pulled from the game and it's over for you. The longest anyone has ever gone on that show was 72 days, and though they won, they had lost a lot of weight, because all they can find in the wilderness is live meat, plants and nuts are not plentiful enough to survive. Not sure what that has to do with our discussion, I just found it fascinating that not even highly trained survivalist can last long, probably around 80 days before they would die. The biggest problem in the wild is finding enough carbs to have energy.
Anyway, I haven't gone long enough to worry about the fruit and vegetable thing yet, but you are correct you do need that on a long tour, however, a human can live a normal life with eating very little in the way of fruits or vegetables. Some societies have lived in areas where they never ate any fruits or vegetables, but their lives are not as long as those that do. But if necessary even on a long tour in the backcountry away from restaurants and Walmarts and you would be just fine without fruits and veggies.
There are freeze-dried veggies you can find, like this:
https://www.amazon.com/gp/product/B0039QW1HM/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B0039QW1HM&linkCode=as2&tag=lizthoadvhik-20&linkId=5VFIYGNR2RZQIA6BI can't eat dark leafy veggies like Kale due to that's one of the things that produces kidney stones in me, so I avoid it, once in a blue moon I'm ok, but not eating it regularly. Also, I have to restrict my protein level somewhat too, because too much protein can cause kidney stones in me as does nuts.
Some cheap freeze dried store-bought food like cup a noodles have dehydrated veggies like peas. There are health and natural stores that sell veggie chips. Also, you can buy green veggie powder supplements but those are a bit pricy but you can get a lot of veggies that take up a very small amount of space. If a person insists on taking fresh veggies then do know this, that for some reason organic veggies tend to last longer without fridging than regular veggies, someone may want to confirm if that's true, but that's what I've heard but it doesn't make any sense to me as to why that would be the case. Seaweed is another good source of veggie that doesn't take up much space, but I'm not sure if I can consume that due to my kidney stone issue, the last thing I want on a tour or camping trip is that mess! The kidney stone issue is why I carry so much water, around 175 ounces, and between drinking it and using it to cook with I can go through all of that in a 24 hour period because even on a normal no riding bike day I try to drink at least 6 16 ounces of water, that's 96 ounces right there, and that's not riding a bike day! So you can see why I need to bring so much water, which is why I try to go to places that have either a camp store or stores nearby so I can buy more water, it's also why I carry a small Sawyer water filter just in case.
So there are ways to get veggies into your diet even if there are no stores around to buy the stuff, carrying fresh veggies takes too much space in a pannier, and there is the question as to how long they'll last, and the reality is you're not going to die unless the tour is going to last 20 years or more and never be near any stores to obtain it along the way, so people would be more than fine going for 6 months out in the boondocks away from fresh veggies and fruit, which I don't think anyone either backpacking or on a long off-road bicycle trip would be anywhere near that many months without getting a hold of fresh veggies and fruit.
