Grapefruit, Vitamins, and Birds' Nests

Both G and I presently have a nasty cold. So, of course, we turn to tea and grapefruit, while discussing the merits of other foods that supposedly help our health. (See http://www.hort.purdue.edu/newcrop/morton/grapefruit.html for more detailed horticultural info on grapefruit). In places like Central and Causeway in Hong Kong, specialty stores sell swallows nest soup (nests made of spit of male swiftlet swallows pried from cave walls in cliffs), which is clear and eaten when one needs a boost to the immune system... it's also supposed to be an aphrodisiac (I think I'll have a section devoted to aphrodisiacs later). G says it's tasteless, so rock sugar or some other flavor needs to be added. Dried nest pieces are soaked in water for several hours, the nests are cleaned of their remnant feathers, then boiled twice. It certainly is a laborious process to make and eat. But are they really that good for you or do you just get that "placebo effect"? I prefer to drink warm tea full of flavanoids with fresh lemon wedges and honey. Likewise, does eating more fruits with water-soluble Vitamin C help boost your immune system? Intaking too much Vitamin C causes diarrhea. Rather, go for a multivitamin like Gummy Vites. They're for children, or the children at heart. In this day and age, we're so spoiled. Remember those Flintstones and Centrum vitamins? Cheers to a more palatable drug industry.