"Better a dish of bitter herbs in a house where there is love than a stalled ox and hatred therewith"

It may be a bit of a leap from that to the fact that onions which don't make you cry when you chop them, do not have the health benefits of those that do.  But it's a fact.

Onion a day keeps doctor away?

Please note that it is the shallot or  onion that brings tears when you cut it, and adds pungency not sweetness to the dish, that is the healthful kind.  I notice that many of the onion available now are the sweeter ones - are we turning into a nation of culinary wimps??

In a wonderful book called "The Cook and the Gardener", about a young American cook who spends a summer at a chateau in France, and finally wins the trust of the ancient French gardener, Amanda Hesser tells of a lady who was NEVER ill, and who would slice a raw onion each day, put it between 2 slices of bread and eat it.  She comments "She was certainly healthy, but I think she had a very loving husband!"