I think this is 23: Lemon and Garlic soup.
It doesn't sound like the most delicious thing ever, but its actually quite nice.
You need some onions, 2-3, finely chopped,
at least one bulb of garlic, peeled and finely chopped (not crushed),
the juice and/or flesh of 3-4 lemons, plus the zest if they're unwaxed,
lots of fresh herbs, such as thyme, chives and parsley,
enough light vegetable stock to make it soupy (or chicken stock if you're that way inclined),
cous cous to make it a little more filling, wholemeal if possible. some precooked quinoa would also be good.
plenty of black pepper.
Ok, fry the onion in a little olive oil til translucent, then add the garlic and lemon flesh. Cook for a few minutes, then add the juice followed by the stock. Bring to the boil, add the cous cous and simmer for 5 minutes, and add the herbs. Serve with plenty of black pepper and maybe a little freshly grated horseradish (for the sinuses). The thing with this soup is that it needs to be freshly made each time as the goodness gets cooked out of it quite quickly.
24 (if indeed the last one was 23): Fruit! I recently started a fruit fast (a few months back actually) and the next day came down with what seemed to be the flu that had that week laid up a large number of people I know. I continued with the fruit (as it was the first stage of a weight loss plan I was starting) and got over the illness within 2 or 3 days. Completely gone. Everyone else had it for at least another week after me!
It was mostly smoothies and juices, and included a homemade spicy pumpkin soup in the evenings, though I think it was mostly the fruit that did it.