1 Pain that does not diminish with rest, and pain that may be worse at night than during the day. 2  Back pain along with constitutional symptoms, such as loss of appetite, unplanned weight loss, nausea, vomiting, or fever, chills or shakes.
Unstable chemicals. Onions produce the chemical irritant known as syn-propanethial-S-oxide. It stimulates the eyes' lachrymal glands so they release tears. Scientists used to blame the enzyme allinase for the instability of substances in a cut onion.
Health Benefits of Onions. Some of the most valuable and well known health benefits of onions are as follows: Good Oral Health: Onions are often used to prevent tooth decay and oral infections. Chewing raw onions for 2 to 3 minutes can potentially kill all the germs present in the oral area and surrounding places like the throat and lips.