Onions

Onions are a very good source 
of vitamins B6 and C, chromium, 
biotin, and fiber.  They are also a 
good source of folic acid and 
vitamins B1 and K.  


The health benefits provided by 
onions are mostly due to their 
content of several organic sulfur 
compounds.  Like garlic, onions 
also have the enzyme alliinase 
(released when an onion is cut or 
crushed).  Other constituents 
that are found in onions include 
flavonoids (primarily quercetin); 
phenolic acids (such as ellagic,caffeic, sinapic, and p-coumaric), pectin, sterols, saponins, and volatile oils.   

Studies have shown that, like garlic, onions and onion extracts decrease blood lipid 
levels, prevent clot formation, and lower blood pressure.  Studies have also revealed 
that onions have a significant effect in lowering blood sugar levels.  Throughout 
history,  onions have also been used to treat asthma.  Their action in asthma is 
mostly due to their ability to inhibit the production of compounds that cause the 
bronchial muscle to spasm, which then causes the muscle to relax.