Kathryn Baecht:You know what I do trust? My own body to protect me. I'm young and fit, and my childhood rickets has almost entirely cleared up. And as far as I can tell, nothing bad has ever happened to a young and fit sailor with just a touch of rickets who heads recklessly off to fight pirates and ghost ships for months on end with nothing for nourishment except barrels of stale, rat-infested biscuits.
So, no, I'm not "afraid" of scurvy. What's the worst that could happen? My teeth will fall out? My bowels will bleed? I'll die at sea, and my body will be cast into the murky depths by my equally moribund shipmates, who won't even have the energy to say a blessing as octopuses and sea monsters feast upon my corpse? That doesn't sound any worse than a little seasickness, and it definitely sounds better than occasionally sucking on a lime. [...]
And while I may be fine, what I am not fine with is the Capitan's new mandate that we must all take this so-called citrus cure. He claims that it's necessary in order to hang onto our already extremely low chance of surviving this harrowing journey through uncharted waters. He says we must do it for our fellow seaman who truly are our brothers. He says we must do it for the common good. He says it is our noble duty. And to that, I say: Screw. Everybody. I'm in it for me and me only.
Listen, if you want to hide below deck licking limes and then later come above deck to enjoy the sunshine and your lack of jaundice and intact teeth and gums that aren't leaking putrid black blood, then be my guest. But not even the Captain has the right to make me eat a nutritious and lifesaving fruit if I don't want to.
Previously, previously, previously, previously, previously, previously, previously.
See also: Scott and Scurvy
If you were actually injecting people with something that changed their DNA, ironically one of the obvious things you could do is permanently eradicate scurvy.
See, the reason that it almost doesn't matter what you eat so long as it's actually fresh, is that almost everything other than us has a working synthesis pathway for "Vitamin C" meaning for them it isn't a vitamin at all. Food animals, fruits, grasses, mushrooms they all make their own, and so are rich in "Vitamin C" from our point of view until we destroy it during preservation. And this isn't some crazy coincidence where every other living thing on Earth learned a trick we don't have, instead one of our distant ancestors (maybe a long dead species of primate since other primates need Vitamin C too) lost this ability and soldiered on without it by eating fresh food.
In theory a relatively small DNA tweak adds back the pathway and the resulting humans would never get scurvy for the same reason we don't get whatever hypothetical disease occurs if you can't synthesise aspartic acid (we can, so, it doesn't).
I guess perhaps the mRNA technology could be used to give you temporary resistance to scurvy (by instructing cells to make ascorbic acid), but like, an orange is cheaper.
https://www.alcademics.com/2018/11/historical-info-about-scurvy-and-the-confusion-between-lemons-and-limes.html
Limes weren't very effective against scurvy.
Also, seventeenth-century British sailors did not have the Internet.