I was trying to keep to 5 cheap foods.
Sorry, I lost track of the "cheap" part of the specifications. Too many years working on government projects.
A question: What about supplements? Like vitamin pills, mineral pills?
In general, as a scientific answer to a scientific question, they work pretty well. I'm lactose-intolerant so I take 150% of the MDAR in calcium tablets. Despite my attempts to be a good boy and eat a healthy diet I just can't stand the taste and texture of a lot of vegetables and besides I really like "comfort food," so I take not only multivitamin-mineral tablets but extra portions of some of the problematic ones like magnesium and antioxidants. But this has been an arduous process and every few years they change the rules.
If a person eats a poor diet, as far as food itself is concerned, how much can this really be fixed by taking supplements?
If the reason you're eating a poor diet is that you're obstinate enough to refuse to eat what's good for you, like I am, then obviously it can work, especially if your wife nags you a lot. If the reason is that you live someplace where the foods necessary for a balanced diet are not available, but by some strange quirk of economics and international trade agreements you can buy vitamins and minerals at a reasonable price, then again you can probably do it.
But if you're avoiding nutritious foods just to save money, it absolutely has to cost you far more money to buy industrially-packaged supplements, than to just buy the right food in the first place. After all, even canned vegetables retain a significant portion of their nutrients--especially if you don't discard the water!--and frozen vegetables are quite high.
I can't promise this for certain, but I'm confident enough that I would definitely bet you an equal amount of money.
You're betting your health, which is not nearly as good a deal.
Taking supplements is not easy, not just a matter of counting out pills and popping them into your mouth. Some vitamins are fat-soluble and if you don't have enough fat in your diet at that time of day they'll just pass right through into your sewage. (Septic tank pumpers talk about the huge volume of undigested vitamin-mineral pills they find in their sludge.) Some minerals, like magnesium have to be taken in the right proportion with other minerals. Some vitamins, like D, and some minerals, like iron, can be toxic in doses that are not impossible to achieve by carelessness or overzealousness.