While I agree with @Ultima that food is a higher priority than recruits, I would try to not lose any recruits. You’ll need them at some point; like all things in E&P, you never have all the materials you want, and somehow, occasionally have more than you need of another material at the same time.
I recommend that when you have oodles of recruits, start to stockpile them in a TC (like 13 or 20). Since those TCs require multiple days to render a hero, with enough recruits and ham, you have this TC continually running.
This, too, requires a lot of ham, but in essence, your TC is like a bank that holds both ham and heroes. Recall that you don’t need to collect your heroes as they are rendered, you can let them sit there so that they don’t clutter/fill your hero capacity. In this way, when you finally get the ascension materials to level up a hero, you can use the heroes from your TC as feeders for the hero you want to max. Since you can also remove heroes from a training camp (just select the minus button), you can also reclaim the ham you were using in that TC, again to level up your hero.
It takes some effort to get all your TCs to have more than a day’s worth of training in their queues, but once you get it going (like right after AR), it can be an effective way to even out the collection and need of materials.