Am / A / F
Geeze! The Chinese, Have been eating these, Prior to 3,000 B.C., That's way before me. Organosulfur, Will you go so far, As to protect me, How soon, Can I be immune? Instantly? I confess, I'm not that Herculean, I surrender, Can you render, The carcinogen, Harmless? What about that ole' wives' tale? I don't wanna expire, Due to some vampire, Do you still, Have the will, To fight off evil? Or, is the devil, In the detail? Allium, Here I am! Onion, I prefer the green, If you know what I mean, When I'm going through, Phytochemical withdrawal, Then, the onion family, Does me, Nicely. (And, they'll do it for you, too. So, go ahead and have one -- Onion.)
NOTES
From Reuters Health
Phytochemicals
Phytochemicals is simply a word that means plant 
chemicals. Hundreds of phytochemicals are currently 
being studied. Many are believed to have a major 
positive impact on human health. Some contribute to the 
bright and vivid colors found in fruits and vegetables. 
The results of studies on specific phytochemicals are 
not necessarily applicable to the vegetables or fruits 
that harbor small concentrations of these chemicals. 
Nevertheless, it is obvious that vegetables and fruits 
are healthful, which is probably due to some balance of 
phytochemicals, carotenoids, vitamins, fibers, and 
minerals rather than any single substance. It should be 
stressed that very little has been proven concerning the 
benefits of phytochemical supplements sold in health 
food stores. Furthermore, high concentrations of some of 
these chemicals may behave like drugs and can be toxic 
and possibly even contribute to cancer cell growth.
Organosulfur Compounds 
Organosulfurs are part of the allium family of 
phytochemicals. Compounds, such as allicin, may have 
benefits on the immune system, assist the liver in 
rendering carcinogens harmless, and reduce production of 
cholesterol in the liver. These compounds are found in 
garlic, leeks, onions, chives, scallions, and shallots.
From Northfields Upper School, UK
Garlic
Allium sativum, with an onion-like smell and pungent 
taste. Its powerful smell has given it a reputation 
around the world as a char against evil characters such 
as vampires, the evil eye, witches, the devil and evil 
spirits. Frequently hung on the person or abode for this
purpose. Medicinally used against any disease, 
particularly those such as plague and malaria that were 
thought to be transmitted in the air. In areas of India, 
(there is a belief that) the colour of garlic can 
eradicate the presence of evil spirits.
From Stanford University
And don't forget the garlic (http://edis.ifas.ufl.edu/MV064)
 It may not keep werewolves and vampires away, but it 
may help "keep the doctor away."
From Me
If you don't want your breath to have a pungent reputation,
you might want to have some parsley for dessert.  Also
to be remembered -- the greens tend to have much less odor
than the bulbs, are filled with chlorophyll and other good stuff.
So, you might want  to start there?