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.
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.
How to Chop and Slice Onions. Rinse the onion thoroughly under cool tap water. On a cutting surface, use a chef's knife to slice off the stem and root ends. Remove the papery outer skins and cut the onion in half from the top end to the root end.