The onion, at one time or another, has been enthusiastically recommended
as a remedy for colds in the head and worms in the intestines. For
centuries, the onion's medicinal value has been praised by witch
doctors, old wives and bartenders. Rome's Pliny the Elder listed the
onion as a cure for 28 diseases. Early New England settlers believed
that the onion would prevent fits; Neapolitans of the Middle Ages
thought it averted the evil eye. A 16th Century French surgeon,
Ambroise Par, used it instead of ointment to heal powder burns.The onion may be coming back into medical fashion. The Russians have
discovered that onion and garlic vapors heal wounds . They called the germ-killing substance a phytoncide . Now Food Chemist Edward F. Kohman has
found that the active chemical agent in onions is a thioaldehyde, a
close relative of the common antiseptic, formaldehyde. Chemist Kohman
put raw onions through an ordinary household meat grinder, distilled
the onion vapors, put them through a series of chemical tests. In a
recent issue of Science, he reported finding about 1/20 of a gram of
thioaldehyde in a pound of raw onions.The germ-killing thioaldehyde, Kohman said last week, probably does not
exist as such in the onion. More likely, it is produced by the
complicated enzyme activity that goes on in the onion when it is cut.
Cooking would eliminate it completely; a boiled onion is no more good
for a cold than a boiled turnip. But chewing a raw onion might help a
cold .
