(This column is one in an occasional series that will discuss health tips that you may have heard, read about or seen on the Internet.)
1) Can drinking grape juice prevent stomach viruses?
There is currently some advice going around on the Internet that drinking a glass of grape juice three times a day after being exposed to stomach flu (gastroenteritis) can prevent a person from getting sick.
The idea is that grape juice’s acidic pH can help suppress the virus, and antiviral chemicals in the juice can help destroy it.
While grape juice is acidic, so are the juices already in our stomachs. The two main viruses causing gastroenteritis, norovirus and rotavirus, are tough and can usually get through our acidic stomachs to infect us.
Making the small intestine have a more alkaline pH may be what helps keep these viruses from infecting us.
Dark grape juice does contain substances called polyphenols that can bind to viral proteins in the laboratory. However, they have not been scientifically studied to see if they can bind to viruses inside our gastrointestinal systems.
Still, polyphenols do provide benefits for our nervous and cardiovascular systems. They also may decrease our risk of getting cancer, so drinking dark grape juice does have some good health benefits.
Just don’t expect it to prevent catching stomach flu.
2) Can eating marshmallows help a sore throat?
Marshmallows were once made using marshmallow root. This root contains mucilage, a thick, gluey substance that can coat, soothe and protect the mucous membranes of a sore throat.
But modern marshmallows are usually made from sugar, water and gelatin. While the gelatin can have a mucousy texture when chewed and swallowed, it is derived from animal material (such as bones and hooves).
While marshmallows may be easy to swallow with a sore throat, they really do not work like the mucilage from marshmallow root.
3) Should one really “feed a cold, starve a fever”?
This idea first appeared in a dictionary written by the schoolmaster John Withals in 1574. At the time, it was thought that food would heat up the body. Conversely, then, avoiding food should help someone with a fever cool down.
The truth is you should both feed a cold and a fever. You need energy from food to help fight off a cold.
Because more calories are burned up with a fever, food is also needed for a fever. Liquids are also important, since an increased body temperature can lead to fluid loss from increased sweating.